Explosions have injured at least nine people at two universities in Beijing.
The blast at a cafeteria at Qinghua University, shortly before noon, injured six people, a university official said.
At nearby Peking University, an explosion in a kitchen at around 1.30 p.m. had slightly injured three people, a university spokeswoman said.
The official Xinhua news agency said earlier the explosion at Qinghua University filled the cafeteria with "the smell of gunpowder" but called it an "accident".
A Foreign Ministry spokesman said police were investigating the Qinghua explosion but that he had not heard of the blast at Peking University.
Qinghua University, also known as Tsinghua, is the alma mater of Premier Zhu Rongji and Communist Party chief Hu Jintao, who is tipped to take over the presidency from Mr Jiang Zemin at the annual session of parliament in March.