Foreign press associations in China expressed alarm Tuesday over recent incidents of intimidation directed against foreign media workers, including the alleged beating of a Japanese journalist.

The Foreign Correspondents' Clubs of Beijing, Shanghai and Hong Kong said they were "extremely concerned" by four recent cases of journalists who had been harassed or subjected to violence while reporting in China.

A joint statement cited the alleged beating of a journalist from Japan's Asahi Shimbun daily by police while covering a demonstration in eastern China in July.

His equipment, worth several thousand dollars, was taken and had not been returned, it said.

Other incidents included an assault on a Hong Kong television reporter outside the court in eastern China where Gu Kailai, wife of disgraced politician Bo Xilai, stood trial for murder this month.

"We are particularly concerned that a number of these incidents have involved members of the official security forces and associated elements," the statement said.

"We call on the authorities at all levels to ensure that journalists are protected from violence and intimidation," the statement said.

China's foreign ministry had no immediate comment on the statement, which came after Al-Jazeera's correspondent in May became the first foreign journalist to be expelled from the country since 1998.

The statement also cited an attack on a German television crew who were accused of being spies and forcibly detained for nine hours at a chemical factory before police escorted them to their vehicles.