PRINCETON – A fire alarm triggered by marijuana smoke went off in one of Princeton University's residential colleges early Wednesday morning, forcing the evacuation of about 100 students, a school official said.

At 1:50 a.m., a fire alarm was set off in a music practice room in the basement of Forbes College, university spokesman Martin Mbugua said. Officers with the Department of Public Safety noticed the smell of marijuana as they approached the room, he said. No one was inside, but a window was open and remnants of marijuana smoking material were found in a garbage bin, he said.

The students were allowed back inside after 10 minutes, Mbugua said.

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