Rule 404(b) provides: Evidence of other crimes, wrongs, or acts is not admissible to prove the character of a person in order to show that he acted in conformity therewith. It may, however, be admissible for other purposes, such as proof of motive, opportunity, intent, preparation, plan, knowledge, identity, or absence of mistake or accident.
See United States v. Rhodes, 779 F.2d 1019, 1030-31 (4th Cir. 1985), cert. denied, 476 U.S. 1182, 91 L. Ed. 2d 545, 106 S. Ct. 2916 (1986); United States v. Bice-Bey, 701 F.2d 1086, 1089 (4th Cir.), cert. denied, 464 U.S. 837 78 L.Ed.2d 123, 104 S.Ct. 126 (1983); United States v. Velazquez, 847 F.2d 140, 143 (4th Cir. 1988). See also United States v. Weddell, 890 F.2d 106, 107-08 (8th Cir. 1989).
Extrinsic or prior act evidence is admissible under Rule 404(b) if the evidence is (1) relevant to some issue other than character, (2) necessary to prove an element of the crime charged, and (3) reliable. See id. Once the evidence has satisfied the above criteria, it may be admitted unless 'its probative value is substantially outweighed by its prejudicial effect.' Id. (internal quotation marks omitted).