A MAN attacked two American tourists, killing one and injuring the other, at an ancient landmark in Beijing on the first day of the Olympic Games yesterday before leaping to his death from the structure, Chinese state media reported.

The Chinese man attacked the two Americans, a man and a woman, and their Chinese tourist guide around 12.20pm on the second level of the Drum Tower, a popular tourist attraction in northern Beijing, the official Xinhua News Agency said.

Todd Bachman, the father of former Olympic volleyball player Elisabeth "Wiz" Bachman and the father-in-law of men's volleyball coach Hugh McCutcheon, was killed in the attack, the US Olympic Committee said in a statement.

His wife, Barbara, sustained "serious and life-threatening" injuries and was rushed to hospital. A female Chinese tour guide with them was also injured. Elisabeth Bachman was with her parents when the attack occurred, but was not injured.

"It is impossible to describe the depth of our sadness and shock in this tragic hour", said US Olympic Committee chairman Peter Ueberroth. "Our delegation comes to the Games as a family, and when one member of our family suffers a loss, we all grieve with them."

Citing the Beijing Municipal Government Information Office, Xinhua said the attacker, Tang Yongming, 47, was identified by an identity card found on his body.

The Chinese government has imposed unprecedented security measures in the capital to prevent protests or other trouble.

US Embassy spokesman Richard Buangan said it was "aware of the reports of the accidents suffered by two American citizens. We are working with the Chinese authorities to find out more on the cause of the incident".

Police blocked off streets leading to the Drum Tower.

Attacks on foreigners in China are extremely rare. A Canadian model was murdered last month in Shanghai, but police said that was because she stumbled on to a burglary. Shanghai and Beijing are still safer than most foreign cities of a similar size.

Built in the 13th century, the Drum Tower is one of the few ancient structures still in Beijing, and was used to tell time in imperial China for the city, using drummers who pounded their instruments to mark the hours. It is on an important central axis of the city, to the north of the Forbidden City, the former home of the emperor.