THESSALONIKI, Greece (AP) — Students occupying a law school during an exam period as a protest against government plans to allow private universities were removed from the building by police in northern Greece. A dozen people were arrested.

A police statement said that the operation followed a request for assistance from university authorities in the town of Komotini. No clashes were reported.

It said the protesters staging the occupation in the law school had prevented about 400 students due to take exams on Monday from entering the building, as well as university staff.

Leftist groups staged protests in Komotini and Thessaloniki against the police operation.

The center-right government wants to legalize privately-run universities in a bill that is due to go before parliament this month. It argues that the reform would prevent skilled people from leaving to study abroad and make higher education more relevant to the labor market.

Opponents say the proposed law would undermine state universities — which provide free tuition — and effectively limit tertiary education to the rich.

Leftist groups and students across Greece have staged a series of building occupations — preventing lectures and exams — and protests against the reform, some of which have turned violent. New demonstrations are planned for Thursday.

The government has urged university authorities to seek police assistance in ending occupations, and to hold online exams in departments that are currently controlled by protesters.