Some 140 law students at the University of London faced an unexpected early end to an exam on Tuesday last week after a bomb threat to Senate House forced an evacuation of the building. An unidentified caller rang reception but hung up abruptly after informing the operator there was a bomb in the basement that would go off at 12.30pm. The area could not be fully searched before that time, so the exam was halted and staff were told not to return to work. There was discussion about allowing students to finish the exam at home, before someone pointed out that was a little impractical. Resits will be held next week. But any student prank callers hoping for extra revision time will be disappointed -anyone absent last week will not be allowed a retake.