Massachusetts activists who oppose the Trump Administration’s violent crackdown on immigrants and protesters are turning to boycotts of businesses connected to the U.S. Immigration and Customs Enforcement agency.

Over the last week, organizers have focused a boycott on Citizens Bank, criticizing the bank’s financing of the two of the country’s largest private operators of immigrant detention centers: CoreCivic and The GEO Group.

Activists have picketed the bank’s branches in Brookline, Cambridge, Lexington, Northampton and other communities, calling on customers to close their accounts.

Support for GBH is provided by:

“They are financing construction of new deportation facilities, like the concentration camps for immigrants,” said Betsy Leondar-Wright, an organizer who formerly taught about social movements as a sociology professor at Lasell University in Newton. “The company managers feel the pressure from all sides, and they realize that it’s going to mess up their reputation and potentially going to cost them business.”

A spokesman for Citizen’s Bank, which is based in Providence, Rhode Island, declined to comment on the boycott and protests on Thursday.

ICE’s killing of two protesters in Minneapolis has added fuel to the boycott, said Leondar-Wright.

“People are just furious at what’s happening around the country, but especially in Minneapolis,” she said.

Close to 90% of the people jailed by ICE are inside private, for-profit companies, according to NPR reporting. Geo Group and CoreCivic are the largest.

Support for GBH is provided by:

GEO Group operates 50 prisons and correctional facilities with more than 60,000 beds in the US. The company has a $629 million contract with ICE for detention centers. CoreCivic runs more than 40 prisons and has won contracts with ICE totaling more than $2 billion.

GEO Group this month announced it had a credit line of $550 million with Citizens. CoreCivic has borrowed $500 million from the bank, according to filings with the U.S. Securities and Exchange Commission.

Leondar-Wright and other organizers pointed to success in the recent boycott and picketing of Texas-based Avelo Airlines, which announced this month it would end its deportation flights for the U.S. Department of Homeland Security.

“Throughout history, boycotts have been one of the strongest tools of successful social movements because unjust authority needs our cooperation to keep going,” she added. “We can non-cooperate by withdrawing our money. As consumers, boycotting is the thing that is within our sphere of influence to do.”

Charles Homer, a retired pediatrician in Brookline, said he joined the boycott effort because he wanted to take specific, concrete action.

The big rallies are very valuable in that they build morale. They demonstrate to the powers that be that there are millions and millions of people that are unhappy and more than unhappy are angry about what’s happening. But protests by themselves are not sufficient,” he said.

Homer said he also volunteers with Chelsea’s La Colaborativa, bringing food to residents who are fearful of leaving home and encountering ICE agents.