East Lyme — State police on Friday charged a second correction officer from the Niantic women's prison with having an illegal sexual relationship with a female inmate, according to detective Sean Velazquez.

Matt Gillette, 43, of Groton was charged Friday with second-degree sexual assault following a five-month investigation into allegations of sexual misconduct by employees of the Janet S. York Correctional Institution, according to a state police news release. 

Gillette surrendered to state police in Montville at noon on Friday following the issuance of an arrest warrant, the release stated. Gillette was released on a $15,000 bond and is due for arraignment at New London Superior Court on April 17.

Velazquez declined to release the home address of Gillette.

Correction officer Jeff Bromley, 46, was charged in February with second-degree sexual assault and has been making regular appearances in court.

Details of the allegations against Gillette were unavailable Friday.

According to an arrest warrant affidavit in Bromley's case, prepared by Velazquez, correction officials reported on Oct. 31, 2014, that a 28-year-old inmate had made sexual assault allegations against three correction officers.

In an interview with state police, the woman said she had sexual contact with the three officers while housed in the Davis building, a housing unit on the east side of the prison campus for inmates participating in an intensive drug treatment program.

The alleged victim provided personal and intimate information about the three officers and said she was concerned that she was two months pregnant by one of them, according to the affidavit. She was treated at the prison's medical unit and tested negative for pregnancy.

The woman said the sexual acts with Bromley occurred in the basement and laundry room of the Davis Building. The basement is locked and off-limits to inmates.  

The accused correction officers were transferred to a different facility and the alleged victim was placed in segregation while the case was investigated, according to the affidavit.

t.townsend@theday.com

Twitter: @ConnecticuTess