The defendant’s first assignment of error relates to the redirect examination of the co-conspirator Pennell and his testimony concerning the threats he received. Re-direct examination may be used to remove any obscurity or uncertainty adduced by the cross-examination. Highway Comm. v. Yarborough, 6 N.C. App. 294, 170 S.E. 2d 159 (1969); 1 Stansbury, N. C. Evidence (Brandis Revision), § 36. However, in the instant case, it appears to go beyond merely explaining the facts elicited on cross-examination. The matters concerning the threats would have been improper on direct examination since there was no connection shown with the defendant. State v. Brantley, 84 N.C. 766 (1881); 1 Stansbury, N. C. Evidence (Brandis Revision), §§ 77 & 78. The witness’ reference to prison conditions did not remove the incompetence of the testimony concerning the threats. However, the defendant also has the burden of showing the objectionable matter to be prejudicial. State v. Brown, 271 N.C. 250, 156 S.E. 2d 272 (1967); State v. Bailey, 12 N.C. App. 280, 182 S.E. 2d 881 (1971). Here there was detailed testimony from the two co-conspirators concerning the defendant’s participation. It is most unlikely that the existence of the threats would make the testimony of the witnesses any more or less believable. While the admission of the threats may have been erroneous, we hold that any error was harmless considering all the testimony.
 The defendant also contends that error was committed by allowing the co-conspirator Hicks to testify that he had given statements to the police concerning his participation in other crimes and that some of these statements did not involve Sneed. Again, considering the testimony as a whole, it is difficult to perceive how this would be prejudicial even if erroneous. Not only must the defendant show error to warrant a new trial; he must also show the error to be prejudicial to the defendant and that a different result would likely have ensued except for the error. State v. Woolard, 260 N.C. 133, 132 S.E. 2d 364 (1963). If there is no reasonable possibility that the error complained of might have contributed to the conviction, the error will be held harmless. State v. Humphrey, 283 N.C. 570, 196 S.E. 2d 516 (1973); State v. Thacker, 281 N.C. 447, 189 S.E. 2d 145 (1972).
In the instant case there is an abundance of evidence to sustain the conviction. The jury clearly believed the testimony *559of the co-conspirators. We hold that the defendant had a fair and impartial trial free from prejudicial error.
Chief Judge Brock and Judge Morris concur.