Bombs that exploded in the dining halls at Peking and Qinghua Universities in Beijing injured six people. The blasts occurred within 90 minutes of each other on February 26 and shattered the sense of security on the normally calm campuses in Haidian district, according to students there. A Beijing Public Security spokeswoman said that the bombs were home-made devices containing black gunpowder, but she declined to say whether the police had any suspects or whether the blasts were thought to be related.