At the close of all the evidence defendant moved for judgment of nonsuit in each case. His first assignment of error is based on denial of these motions. He contends the motions should have been allowed with respect to the charges of murder in the first degree because “no evidence was presented during the trial which related to the elements of premeditation and deliberation, either by direct proof or by any other inference or circumstance.”
 “Premeditation and deliberation are not usually susceptible of direct proof, and are therefore susceptible of proof by circumstances by which the facts sought to be proved may be inferred.” State v. Walters, 275 N.C. 615, 170 S.E. 2d 484 (1969) ; accord State v. Duboise, 279 N.C. 73, 181 S.E. 2d 393 (1971) ; State v. Reams, 277 N.C. 391, 178 S.E. 2d 65 (1970).
 “Among the circumstances to be considered in determining whether a killing was with premeditation and deliberation are: want of provocation on the part of the deceased; the conduct of defendant before and after the killing; the use of grossly excessive force, or the dealing of lethal blows after the deceased has been felled. See State v. Walters and cases cited, 275 N.C. 615, 623-24, 170 S.E. 2d 484, 490 (1969). See also State v. *130 Johnson, 278 N.C. 252, 179 S.E. 2d 429 (1971).” State v. Van Landingham, 283 N.C. 589, 197 S.E. 2d 539 (1973).
 Evidence offered by the State tends to show, inter alia: Mr. Powell died as a result of gunshot wounds — two in the chest with one bullet piercing the heart, and one in the head. Each bullet wound was potentially fatal and the temple shot was fired after the shot through the heart and at a time when Mr. Powell was dying. Mrs. Powell was shot once in the upper abdomen and once in the chest, the latter shot piercing the heart.
Both victims had severe head lacerations. Mr. Powell had five deep scalp wounds, some of which exposed the skull. Mrs. Powell had two deep scalp wounds, both of which exposed the bone. Examination of these wounds indicated to Dr. Wood that “they were struck with a blunt instrument several times in a frenzy.” In the opinion of Dr. Wood the head wounds were inflicted before the gunshot wounds.
Mrs. Powell’s body was found in a sitting position in the bathroom. The officer who found the body “observed a piece of metal, which appeared to be a piece of the door lock, lying on the bathroom floor. The door facing appeared to be splintered. The door was slightly ajar, and it appeared it was split down the section where the lock is placed on the door.”
The ingredients of premeditation and deliberation necessary in first degree murder may be inferred from the vicious and brutal circumstances of the homicide. The evidence here shows a complete lack of provocation and a viciousness which demonstrates that death was the actor’s objective. The deadly shots through the heart after each victim had been felled and rendered helpless by mortal blows to the head support, almost require, the legitimate inference of premeditation and deliberation. This evidence is sufficient to repel the motions for nonsuit and require submission of the cases to the jury on the issue of murder in the first degree. State v. Duncan, 282 N.C. 412, 193 S.E. 2d 65 (1972) ; State v. Duboise, 279 N.C. 73, 181 S.E. 2d 393 (1971); State v. Reams, 277 N.C. 391, 178 S.E. 2d 65 (1970) ; State v. Perry, 276 N.C. 339, 172 S.E. 2d 541 (1970) ; State v. Faust, 254 N.C. 101, 118 S.E. 2d 769 (1961). Defendant’s first assignment of error is overruled.
 Over defendant’s objection the solicitor was permitted to propound the following question to Dr. Robert Rollins, Superin*131tendent of Dorothea Dix Hospital, a medical expert specializing in the field of psychiatry: “Based upon your own personal examination and interview of Karl DeGregory, and any other information contained in his official record of which you were the custodian and had available to you, did you make a diagnosis of the defendant?” Defendant’s objection to the italicized portion of the question was overruled and defendant assigns as error the ruling of the court in this respect. Dr. Rollins replied: “Yes I did. For the purposes of our report back to the court, the psychiatric diagnosis was without psychosis; that is, not insane, that Mr. DeGregory was competent to stand trial. . . . Karl DeGregory was assigned to Dorothea Dix Hospital for examination purposes for approximately two months. Based upon my own examination, I am of the opinion that Mr. DeGregory is not a paranoid schizophrenic. I have some general knowledge of the circumstances surrounding the crime with which Karl De-Gregory is charged.” On cross-examination, Dr. Rollins testified: “Personally, I spent about three hours with Karl DeGregory. My testimony is predicated on the three hours which I spent with Karl DeGregory and upon the information furnished me by members of my staff. I spent three separate occasions with Karl DeGregory. Mr. DeGregory was responsive to my questions. I had the feeling at times that he was not answering with the completeness that I might have liked, but I thought that not unusual for a person in his situation. ... I was not treating Mr. DeGregory. I was just diagnosing. ... [I]n some aspects of the evaluation, it’s just as important to observe what the patient doesn’t say or how he avoids a question as to how he answers. Other than presenting as comprehensive a report as possible, I don’t actually think that any of the tests run were necessary to perform, in my opinion. I do not think the Rorschach test or the MMPI test was necessary. I am satisfied that Karl DeGregory was not criminally insane based upon my three hours with him. . . . [T]he existence of mental illness is not synonymous with not being responsible for what you do. The following quote satisfies my definition of criminal responsibility but not my definition of insanity: ‘An accused is legally insane and exempt from criminal responsibility by reason thereof if he commits an act which would otherwise be punishable as a crime and at the time of so doing is laboring under such a defect of reason from disease of the mind as to be incapable of knowing the nature and quality of the act he is doing, or if he does know this, incapable of distinguishing between right and wrong in *132relation to such act.’ . . . Paranoids are capable of murder. Schizophrenics are capable of murder. Paranoid schizophrenics are capable of murder and are capable of suffering- from amnesia afterward.”
Defendant asserts that Dr. Rollins based his expert opinion “on information obtained by someone else, which information was inadmissible in evidence,” and cites the following quotation from State v. David, 222 N.C. 242, 22 S.E. 2d 633 (1942), in support of his contention that this was error prejudicial to his insanity defense: “There are two avenues through which expert opinion evidence may be presented to the jury: (a) Through testimony of the witness based on his personal knowledge or observation; and (b) through testimony of the witness based on a hypothetical question addressed to him, in which the pertinent facts are assumed to be true, or rather, assumed to be so found by the jury.” We now explore the validity of this assignment.
Defendant’s interpretation of the quotation from State v. David, supra, is too limited. The quotation states that an expert may base his testimony on facts within his personal knowledge or observation, or may base his opinion on facts presented in a hypothetical question, but it does not purport to limit facts and information within the personal knowledge of an expert to knowledge derived solely from matters personally observed. As demonstrated in opinions of this Court since State v. David, supra, an expert witness has wide latitude in gathering information and may base his opinion on evidence not otherwise admissible.
In Penland v. Coal Co., 246 N.C. 26, 97 S.E. 2d 432 (1957), the testimony of a physician was challenged because his opinion was based on statements made to him by the patient during the course of a professional examination. We noted that although the statements of the injured patient were “not admissible as evidence of the facts stated, [they could] be testified to by the physician to show the basis of his opinion,” and held that it is permissible for a physician to base his opinion, wholly or in part, on such statements, if made by the patient in the course of professional treatment, or during the course of an examination made for the purpose of treatment and cure.
In Highway Commission v. Conrad, 263 N.C. 394, 139 S.E. 2d 553 (1965), speaking to the competency of expert witness *133testimony in a condemnation proceeding, we quoted with approval the following language from 5 Nichols on Eminent Domain, 3d ed., § 18.42(1), p. 256: “The fact that certain elements áre not independently admissible in evidence . . . does not bar their consideration by an expert witness in reaching an opinion. Thus, it has been said: ‘An integral part of an expert’s work is to obtain all possible information, data, detail and material which will aid him in arriving at an opinion. Much of the source material will be in and of itself inadmissible evidence but this fact does not preclude him from using it in arriving at an opinion. All of the factors he has gained are weighed and given the sanction of his experience in his expressing an opinion. It is proper for the expert when called as a witness to detail the facts upon which his conclusion or opinion is based and this is true even though his opinion is based entirely on knowledge gained from inadmissible sources.’ (People v. Ganghi Corp., 194 C.A. (2d) 427, 15 Cal. Rep. 25).” In accord with these expressions is State v. Arnold, 341 P. 2d 1089 (Ore. 1959).
In Potts v. Howser, 274 N.C. 49, 161 S.E. 2d 737 (1968), we held it proper to allow a medical expert to give his opinion as to what was shown by a radiologist’s report and the accompanying X-rays used by him in diagnosing plaintiff’s injuries but not introduced into evidence.
Federal courts have held that a psychiatrist’s testimony based on hospital records together with his own observation of defendant is admissible. United States v. Davila-Nater, 474 F. 2d 270 (5th cir. 1973) ; Birdsell v. United States, 346 F. 2d 775 (5th cir.), cert. denied, 382 U.S. 963 (1965), and cases cited therein.
In Birdsell the defendant contended that the testimony of a psychiatrist as to defendant’s sanity, based upon a personal interview with the defendant and examination of defendant’s tests, case history and hospital records, was inadmissible. Judge Friendly, writing for the court, first noted that prior decisions had established that opinions as to sanity contained in hospital records are not admissible under the Business Records Act, 28 U.S.C. § 1732, but that such an opinion is admissible in evidence if the expert rendering it is made available for cross-examination. The. court then stated that while the records of a hospital performing psyschiatric investigations with respect to the symptoms recounted by the subject or the results of recognized *134psychological tests may, unlike records of many physical symptoms, be useless to a jury and be excludable on that ground, “there is abundant authority that an expert witness who is available for cross-examination at the trial may use such records as the basis of an opinion without the proponent having to call every person who made a recorded observation. [Citations omitted.] With the increased division of labor in modern medicine, the physician making a diagnosis must necessarily rely on many observations and tests performed by others and recorded by them; records sufficient for diagnosis in the hospital ought to be enough for opinion testimony in the courtroom.” Birdsell v. United States, supra.
On these authorities, and on reason as well, we hold it was proper for Dr. Rollins to base his expert opinion as to the sanity of Karl DeGregory upon both his own personal examination and other information contained in the patient’s official hospital record. The question was proper and the answer was competent.
We note, moreover, that even had defendant been correct in his assertion that an expert cannot base an opinion on personal examination plus inadmissible information obtained from other sources, defendant could not prevail on this assignment. Even though the question put to Dr. Rollins sought his diagnosis of defendant based upon both his personal observation of defendant and information contained in defendant’s records at Dorothea Dix Hospital, his testimony discloses that his opinion of defendant’s sanity is based strictly on his own personal observation of defendant. At one point Dr. Rollins said: “Based upon my own examination, I am of the opinion that Mr. DeGregory is not a paranoid schizophrenic.” Later, on cross-examination, he made the following statement: “I am satisfied that Karl DeGregory was not criminally insane based upon my three hours with him.” Although Dr. Rollins did at one point in his testimony state that his testimony was based on both his personal interview with Karl DeGregory and information furnished by his staff, it is clear that on the crucial question of Karl De-Gregory’s sanity, he based his testimony solely on his personal observation of defendant. It thus appears that defendant has not been prejudiced by the doctor’s testimony even under the more restrictive view of the law urged by defendant. This assignment is overruled.
*135Defendant having failed to show prejudicial error, the verdict and judgment in each case must be upheld.