Students at Bates College waited anxiously for news under lockdown.

At Bates College, the active shooter alert on Wednesday night interrupted a birthday celebration in a dormitory room.

The alarm, at about 8 p.m., prompted Mavy Le, 19, and 11 of her friends to take the elevator up to a higher floor. Instinct told them to get to higher ground and away from windows.

“We huddled together and waited for more news,” Ms. Le said in an interview early Thursday.

The lockdown remained in place overnight for Lewiston, Me., and the 1,800 students at Bates College, a small liberal arts institution there.

The emergency order left some students and employees stranded on campus, unable to return home, the university said in a statement. The threat of an active shooter at large also forced the school to cancel classes on Thursday.

“We know that these events have shocked and frightened our community,” a vice president at the college, Geoffrey Swift, said in the statement.

As Ms. Le waited for news in her dormitory, her family in the Portland, Me., area periodically checked in with her, she said.

At about 1:30 a.m., she was trying to distract herself from the anxious situation by studying for exams and doing her assignments — although it was not easy to focus, she said.

“My shades are completely rolled down,” she said. “I’m trying not to look outside.”