Chinese police have detained a prominent 70-year-old journalist just weeks ahead of the 25th anniversary of the Tiananmen Square crackdown for allegedly leaking state secrets to a website outside the mainland, state media reported Thursday.

Police in Beijing placed the outspoken veteran journalist Gao Yu under "criminal detention," the official Xinhua News Agency said. Gao was the latest of detention of government critics in recent days ahead of the politically sensitive June 4 anniversary. Several had attended a seminar on Saturday to discuss Tiananmen Square.

The report said the journalist was detained April 24, with authorities seizing evidence at her Beijing home. Gao was a well-known government critic who was imprisoned after the 1989 crackdown and had been reported missing since April 26. The report said Gao had confessed to the misdeeds.

State broadcaster CCTV showed in a report a woman the network identified as Gao, wearing an orange vest over a grey detainee's uniform, walking along a hallway escorted by two police officers to a room where she appeared to be questioned. The woman's was blurred.

State media reports did not detail the authorities' accusations against Gao but said she had provided a "secret central party document" to a website outside the mainland.

Human Rights Watch Asia researcher Maya Wang said Gao's detention, following several other detentions of prominent dissidents earlier this week, pointed to the great lengths to which authorities were prepared to go to deter activities that would mark the military suppression of pro-democracy protests in 1989. Gao had been arrested on June 3, 1989, just before the crackdown.

Gao had been convicted of leaking state secrets in 1994 in a secret trial and sentenced to six years in prison, of which she served more than five before being released on medical parole.

On Tuesday, Chinese authorities detained well-known rights lawyer Pu Zhiqiang and several other people in an apparent bid to deter activists from marking the anniversary of the military suppression of pro-democracy protesters. Pu's associate Qu Zhenhong said the lawyer was detained Tuesday morning. Pu had attended the Saturday seminar, along with Beijing-based scholars Hao Jian and Xu Youyu and blogger and free speech activist Liu Di, who were similarly detained Tuesday, Hu said, citing reports from family members.

The Associated Press