RALEIGH, N.C. (AP) - Police in North Carolina's largest city have charged a registered sex offender with raping two teenagers more than 20 years ago based on evidence obtained through DNA testing of old sexual assault kits.

Charlotte-Mecklenburg police told a news conference Wednesday that 56-year-old Warren Lee Caldwell was arrested March 1 and jailed in connection with the rape of an 18-year-old in 1990 and of a 17-year-old in 1994.

Sgt. Darrell Price says the department received two grants to pay for the testing of sexual assault kits.

Caldwell is behind bars, charged with two counts of second-degree rape and one count of first-degree kidnapping. It wasn't clear Wednesday if he has an attorney.

The arrest was announced the week after state officials said North Carolina has more than 15,000 untested rape kits.