Twelve demonstrators protesting Amazon’s contracts with Immigration and Customs Enforcement were arrested on trespassing charges Thursday after reportedly refusing to leave the lobby of the online retail giant's office in Cambridge, Massachusetts, police said. Hundreds of activists marched to the Amazon office from downtown Boston chanting slogans like, “Never again means abolish ICE.” Video from Amazon’s office showed a crowd of protesters blocking the elevators, prompting police officers to escort employees through. The demonstrators left a banner outside the building that read, “Never Again means # No Tech for ICE,” according to The Boston Globe. Some Amazon employees have previously expressed concerns about the data-mining company Palantir—which is used by ICE —operating on Amazon Web Services. The organizers of the demonstration, Never Again Action, a group of Jewish activists, have staged several protests against immigration detention since they formed about two months ago—including one in August in which a Rhode Island prison staffer drove his truck into the group as they protested against the prison’s cooperation with ICE.