AURORA, Colo., June 26 (UPI) -- The police department in Aurora, Colo., made a "big mistake," destroying DNA evidence from at least 48 rape cases, Police Chief Dan Oates says.

Oates announced the inadvertent destruction at a news conference Tuesday, The Denver Post reported.


He said all of the cases dated from 2009 and evidence was destroyed during several months beginning in January.

"Obviously this is not a good day for the department," Oates said. "This is a big mistake."

In at least one case, Oates, said, investigators had identified a suspect from the DNA. In other cases, victims had called off the investigation or finding a perpetrator appeared unlikely.

Oates said he met with one victim before the news conference. He described her as "gracious and understanding -- more understanding than I would have been in that situation."