A Chester County police officer sexually abused three girls repeatedly over nine years, often at his home, according to charges announced yesterday.

Kennett Square Officer Jose Manuel Santiago, 54, was being held without bail in New Castle, Del., after his arrest Thursday at a home in Newark, Del.

The girls went to authorities in August to report that they had been abused from 1991 to 2000. All three were under age 14 when the abuse began, according to a police affidavit.

Two of the girls were relatives, while the third spent significant time in Santiago's care at his home in Toughkenamon, the affidavit said.

Santiago has been employed by the police department since 1995 but has recently been out on disability unrelated to his job, the department said. Two years ago, the patrol officer earned a borough commendation for volunteering his time to help with an FBI kidnapping case.

Santiago was charged with more than 500 sex-offense counts, including rape, incest, statutory sexual assault and endangering the welfare of children in his care.

One girl said he sexually assaulted her daily during her teen years. The abuse started when she was 11 and continued through age 18, she said.

There is no evidence Santiago used his position as a police officer to pursue his alleged victims, authorities said. He has been suspended with pay pending an internal investigation, Mayor Matt Fetick said.

Santiago was being held in the New Castle County prison and was fighting extradition to Pennsylvania, borough solicitor Marc Jonas said yesterday. It was not clear if he had an attorney.