CAMBRIDGE, Mass. (AP) — Police detained several people Thursday at the Massachusetts Institute of Technology after demonstrators blocked a parking garage in their ongoing protest movement connected to the Israel-Hamas war.

Tensions have ratcheted up in standoffs with protesters on campuses across the United States and increasingly in Europe. Some colleges cracked down immediately, while others have tolerated the demonstrations. Some have begun to lose patience and call in the police over concerns about disruptions to campus life and safety.

In Boston, the U.S. city most identified with higher education, students have set up encampments on at least five campuses, including MIT, Northeastern University and Harvard University.

At MIT, protesters have been asking administrators to end all research contracts with Israel’s Ministry of Defense, which they estimate total $11 million since 2015. On Thursday, the school issued an alert just before 2 p.m. saying protesters were blocking the entrance to a campus parking garage and spilling onto a nearby street.

About two hours later, authorities split protesters up and pushed them away from the garage. At least three people were detained. Protesters walked away continuing to chant “free Palestine.” The crowd dispersed, and the garage was reopened by 5 p.m., the school said.

Hannah Didehbani, an MIT student and one of the leaders of the protest, said the decision to block the garage was part of a larger effort to bring attention to what she described as MIT’s complicity with the Israeli military. Didehbani said she has been issued a suspension and an eviction notice by the school but said MIT cannot suspend the larger student movement.

“They’d much rather do those things than cut ties to a state that is currently enacting a genocide,” she said.

The pro-Palestinian protest movement began nearly three weeks ago at Columbia University in New York City. It has since swept college campuses nationwide, with more than 2,500 people arrested.