EXILED labour activist Han Dongfang set up camp on the border between Shenzhen and Lowu last night after Chinese guards refused his repeated attempts to cross into the mainland.
Making his second attempt in two days to return to China, Mr Han passed through the Hong Kong border at about 6 pm but was turned back by the officials on the Chinese side.
Mr Han unrolled a sleeping bag on the bridge crossing the Shenzhen river, which divides Hong Kong from the Special Economic Zone, where he tried to spend the night.
Travellers returning from China last night at Lowu said three green uniformed officers from the Chinese Security Bureau appeared to be standing guard over the exiled unionist.
But the witnesses said Mr Han had been treated politely by the Chinese authorities, who did not at first make any attempt to move him.
Legislator and pro-democracy activist Lau Chin-shek crossed through the Hong Kong checkpoint in an attempt to assist Mr Han late last night but it was not clear if he would be allowed to cross into China.
Earlier yesterday Mr Han's supporters had vowed that he would make every effort to return to his native China even though he had been stopped from boarding a Beijing bound flight on Thursday.
Mr Han had said the more often he tried to return to China the more likely he was to succeed.
Last night was the third time he had tried to return to the mainland since he became stateless in August.
He was expelled from Guangzhou after returning from the United States where he underwent treatment for tuberculosis.
Chinese officials who expelled him allowed him to keep his passport but the Public Security Ministry has since made known its decision to cancel it through Xinhua (the New China News Agency).
Yesterday, the head of Hong Kong's American Chamber of Commerce rebuked China over barring Mr Han, saying it cancelled out a positive move in the campaign to renew Beijing's Most Favoured Nation (MFN) trade status.
Speaking after a visit to Beijing, AmCham chairman Lyn Edinger said the Chinese leadership's failure to pursue consistent policies on key issues such as human rights hampered progress in Sino-US relations.
''You have this frustrating situation where something that is obviously intended as a good, and positive, and conciliatory gesture is cancelled out by an action that appears to be so contradictory to it,'' he told a news conference.
In a hint at a possible compromise in its bitter human rights dispute with the United States, this week Foreign Minister Qian Qichen said China might allow the Red Cross to visit its prisons.
Mr Edinger, who led an 11-strong delegation to Beijing this week, quoted officials as saying China was prepared to discuss human rights but not in the context of trade.
''MFN is by no means certain in 1994. The human rights element has to be addressed. We will gear up for another major campaign,'' he said.