RICHMOND — Amid a growing national outcry against ICE stoked by recent scenes of families separated at the U.S.-Mexico border, the Contra Costa Sheriff’s Office on Tuesday is expected to announce that its multimilllion-dollar federal contract to detain undocumented immigrants in a Richmond jail will be cancelled, according to a knowledgeable source within the county.

A local immigrant advocacy group that requested anonymity confirmed it was provided the same information by a county source. The sheriff’s office declined to comment.

Richmond Mayor Tom Butt said he has heard some reports that the Board of Supervisors and the sheriff’s office were working on an agreement to end the contract, but he wants to hear details.

“I think it would certainly deflate a lot of concerns of a lot of people if the sheriff got out of the detention business,” Butt said.

In April, Butt requested a tour of the West County Detention Facility in Richmond after learning of allegations that detainees were being mistreated. The sheriff’s office denied Butt’s request at the time, but he has since been given approval to visit the facility on Wednesday.

The sheriff’s office entered into a contract with the U.S. Marshals Service in 2009 to house undocumented immigrants awaiting hearings at the detention facility. As part of that contract, Immigration and Customs Enforcement (ICE) pays the sheriff’s office $82 per detainee a day. According to the sheriff’s office, an average of 200 people are detained at the jail daily.

Through the arrangement, the county annually collects about $6 million, netting a profit of $3 million, according to the sheriff’s office’s website.

The contract can be cancelled at any time as long as the federal government is given 120 days advance notice.

The West County Detention Facility is the only Bay Area jail that houses undocumented immigrants. It’s unclear what will happen to detainees if the contract is cancelled.

In early June, the Sacramento County Board of Supervisors voted not to renew a five-year-old contract with ICE that housed detainees at the Rio Cosumnes Correctional Center in Elk Grove. Three supervisors went against the sheriff’s recommendations and voted against renewing the agreement, citing ethical grounds and the political climate.

If the Richmond facility becomes off limits for undocumented immigrants, the closest detention facility would be the Yuba County Jail in Marysville.

According to Syracuse University’s Transactional Records Access Clearing House, 960 immigrants were detained at the Richmond jail between October 2014 and September 2015. Of those, 40 percent left the facility, mainly through posting a bond, and 60 percent were transferred to another facility.

The potential cancellation comes in the wake of mounting pressure on Sheriff David Livingston from community groups, residents and elected leaders to end the ICE contract. Sustained protests outside of the Richmond jail have grown larger in recent weeks.

The California Values Act, a new law that went into effect in January, bars local law enforcement agencies from cooperating and communicating with ICE.

In March 2016, the Contra Costa County Sheriff’s Office issued a memo to all staff stating it would no longer honor requests from ICE to hold detainees beyond their regularly scheduled release dates. However, the office found loopholes in the law that allowed it to notify ICE when a detainee was scheduled to be released.

On March 29, this news organization reported that the sheriff’s office had begun publicly posting release dates of inmates, including detained immigrants, on its website. To view the sheriff’s office’s policy and procedures online, go to bit.ly/CoCoSoGPP