Louisville, Ky. ? A grand jury indicted two police detectives on hundreds of charges of misconduct, including allegations they tampered with drug evidence and forged judges’ signatures on warrants.

The cases, reminiscent of a scandal that racked a Los Angeles anti-gang unit in the late 1990s, could result in the dismissal of charges and verdicts being overturned, officials said.

The two Jefferson County Metro Narcotics detectives, Mark Watson and Christie D. Richardson, were arrested Thursday and charged in a 472-count indictment, said Jeff Derouen, a spokesman for the Jefferson County commonwealth’s attorney’s office.

Both pleaded innocent at their arraignments Friday and were freed on bond, a mix of land parcels and $25,000 cash each.

Derouen said the detectives had been under investigation by the FBI and U.S. attorney’s office for repeated absences at scheduled court appearances.

A criminal investigation launched by the Jefferson County police looked into whether the detectives fabricated information to obtain search warrants, tampered with drug evidence, took money intended for informants and forged judges’ signatures on warrants.

The indictment involved 24 cases the detectives had worked on.