BOSTON — Boston’s sheriff is ending his office’s longtime relationship with U.S. Immigration and Customs Enforcement, saying his jails will stop housing hundreds of federal detainees in order to house more female inmates.

Suffolk County Sheriff Steven Tompkins maintained the move, which he announced late Tuesday, is not a political statement but an effort to improve the lives of incarcerated women, which he said is the fastest-growing incarcerated population in the country.

ICE has had a contract with the Suffolk County Sheriff’s Office since 2003, but the Suffolk County House of Correction, which is sometimes referred to as South Bay jail, has become a focal point of local protests against President Donald Trump’s immigration policies in recent years.

“We take pride in the services that we have been able to provide to ICE detainees,” Tompkins said in a statement. “But we are elated about this new opportunity to expand our services across the Commonwealth of Massachusetts to reach more women with our dedicated programming so that we can begin to work on their recovery, address some the issues that first led them into the system, and return them to society better able to care for themselves and their families.”

The jail’s decision will have a “huge impact” on ICE’s day-to-day operations as the facility is close to federal immigration court and Logan International Airport in Boston, said Todd Michael Lyons, the agency’s New England deputy director.

Most federal detainees at the Boston jail are “high-level category offenders,” including people convicted of violent felonies and gang members, he said.

The agency said detainees will now have to be placed in other Massachusetts jails or elsewhere in the country, potentially impacting the ability of families or lawyers to visit in person.

The American Civil Liberties Union of Massachusetts applauded the sheriff’s decision but said it would be a “disservice” to Massachusetts families if the decision led to the creation of new detention space or resulted in detainees losing access to their families and legal representation.

Tompkins said federal authorities are expected to complete the transfer of about 200 federal detainees by mid-December.

He said the jail will begin receiving female inmates from Essex, Norfolk, and Plymouth counties this week as part of a new effort to regionalize services. He said the women will be enrolled in the jail’s specialized programs, which work to address issues such as domestic violence, sexual exploitation and substance use in order to better prepare them for release.

The South Bay jail currently houses about 1,200 inmates, of which about 200 are ICE detainees and nearly 100 are female inmates.

Comments are not available on this story.