Chinese police are reported to be on alert as Tibetan Buddhists begin celebrating the Saga Dawa festival (Buddha's birthday) in Lhasa.
The month-long festival began Wednesday. It marks the birth of the Buddha, according to the Tibetan calendar.
Traditionally, pilgrims from all across Tibet converge on the capital city of Lhasa for a month of celebrations and public gatherings.
News reports from Lhasa this week said armored police have been deployed on the city streets in preparation for the festival.
The French news agency quotes a Chinese government spokesman as saying that security has been tightened because of threats made by Tibetan separatists. The spokesman did not specify the nature of those alleged threats.
China also is readying for the Tibet leg of the Olympic torch relay. The torch will pass through Lhasa on June 19th.