A reporter and photographer from two Japanese news organisations were detained and beaten by Chinese police as they were covering yesterday's terrorist attack on a police station in Xinjiang province, the organisations said.

Uighur separatists killed 16 police when they attacked a police station using a truck, home-made explosives and knives.

The two organisations said Masami Kawakita, a 38-year-old photographer from the Chunichi Shimbun newspaper's Tokyo headquarters, and Shinji Katsuta, a 37-year old reporter from Nippon Television Network's China General Bureau, both suffered light injuries.

The two men arrived in Kashgar late on Monday and were stopped by force when covering the incident.

They were allegedly taken inside a nearby hotel, and were beaten before being released two hours later.

Japan plans to protest to China over the alleged detention and beating by police, a top government official said.

"Our embassy is of course gathering information from the authorities," said Japan's top government spokesman, Nobutaka Machimura.

"I believe there is no mistake, so we plan to protest strongly."

Police may have detained the reporters on suspicion that they were taking pictures of a nearby military facility, said spokesman Kenji Kikata of Nippon Television.

"It is extremely unfortunate that a working reporter who followed the correct procedures should be the victim of violence," the company said in an official statement.

Chinese police have arrested two ethnic Uighurs, members of a minority that resents Chinese control of the region, for Monday's bomb attack, which marred the final countdown to the Olympics.

Japan's Prime Minister Yasuo Fukuda, a long-term advocate of warmer ties with China, is set to attend the opening ceremony in Beijing on Friday.

- Kyodo/Reuters