Zhang Lin, who played a leading role in 1989 pro-democracy protests in eastern Anhui that mirrored those held in Beijing's Tiananmen Square, was arrested on his return from the capital late last month, activist Ren Wanding said.

Zhang's detention, a week after other activists were able to get to Zhao's house to mourn him, signals Beijing's desire to keep a lid on emotions stirred by the death of the former leader.

``He came to Beijing on January 28 to go to Zhao Ziyang's house, but was not allowed in, so he went back to Anhui the next day,'' Ren said in Beijing.

``After going back to Bengbu, he was seized by the police and held for 15 days and his computer taken. Today his wife and friends went to pick him up, but the police said he had already been detained for threatening state security and sent to jail.''

A family friend at Zhang's house in Bengbu said relatives were not able to pick him up.

``It's very strange. We don't know why they are doing this. We went to meet him but were unable to,'' the friend said. ``We don't know where he is.''

Zhang, jailed for two years for his role in the 1989 protests, left for exile in the United States in 1997 but stole back into China in November 1998. He was arrested and sentenced about a month after that to three years of hard labour and re-education for illegal entry.

Zhao died in a Beijing hospital on January 17 at the age of 85 after spending 15 years under house arrest for opposing the army crackdown in Tiananmen Square.

Nervous that Zhao's death might trigger protests, the leadership tightened security in the capital and permitted only a scaled-down funeral for the man who, as premier in the 1980s, launched market reforms that turned the country from a centrally planned backwater into a fledgling economic powerhouse.

REUTERS