Some 500 Tibetan separatists on Monday gathered outside the Chinese embassy in Washington, and attacked the embassy, embassy officials said Tuesday.

The separatists chanted slogans and waved flags and placards supporting "Tibet independence." Many of them turned violent, throwing stones at the embassy building, and trying to break into the embassy. Some windows of the embassy building were broken.

Two of the separatists were arrested by the police. A U.S. secret service officer suffered minor injuries while preventing the separatists from passing through the barricade.

The separatists were dispersed by police and later left the embassy on several buses.

The violence is one of a series of similar attacks on Chinese diplomatic missions abroad before and after the Lhasa riots on March 14, which the Dalai Lama and his followers have been claiming to be "peaceful" and "non-violent."

Since March 10, there have been violent attacks on 18 overseas diplomatic missions of China by "Tibet Independence" separatists and those with international "Tibet support" organizations, according to the spokesman for the Ministry of Public Security of China.

The criminal violence in Lhasa on March 14 has left 18 innocent civilians dead, Wu Heping told a press conference in Beijing on Tuesday.

Editor: Yan