Beijing (AsiaNews/Agencies) - State security police have stepped up surveillance of political dissidents ahead of the anniversary of the June 4 crackdown on pro-democracy protesters in Tiananmen Square 16 years ago

"Officials from the Beijing state security bureau came to my house yesterday," said Ding Zilin, leader of the "Tiananmen Mothers". "They interrogated my husband for about 30 minutes. They wanted to know about the open letter that we sent to President Hu Jintao."

After the "visit" police had told the group not to carry out any activities for the anniversary.

In an open letter sent to Chinese president the group says are "meaningless" the recent protests by the Beijing government against Japan for its too-bland admission of World War II atrocities perpetrated in China, because "the Chinese government itself has not yet asked pardon for atrocities it perpetrated."

The "Mothers of Tiannamen" is a group composed of 125 families of victims of the disaster in Tiannamen Square on 2 June 1989, when troops of the national army backed by tanks, massacred defenceless protesters. For more than a month, the demonstrators had been calling for democracy and an end to corruption for Chinese society in the streets of the Chinese capital.