A protest mission to Beijing launched by the League of Social Democrats suffered a setback last night when veteran activist Lo Chau was led away by police at Beijing airport despite being allowed to take a flight to the capital from Shenzhen after crossing the border.
Mr Lo was released at about 9pm after being detained for almost three hours. He said he was not questioned or given an explanation for his detention.
He said he would write a letter and present it in a petition today to the NPC complaints office calling for universal suffrage in 2012.
He became the sole protester after three of his colleagues were turned away at the Lo Wu checkpoint.
'I hope the NPC Standing Committee will respect Hong Kong's hope for the introduction of universal suffrage by 2012. I will take the message to the NPC's complaint office,' Mr Lo said after arriving in Beijing.
Almost immediately after being greeted by the media, Mr Lo was led away by more than 30 uniformed and plainclothes public security officers.
He was not seen again before being freed.
Mr Lo - a veteran activist from the movement to demonstrate Chinese sovereignty over the Diaoyu Islands, which are also claimed by Japan - was the only protester with a home-return permit on the four-member team which tried to enter Shenzhen.
The others - legislator 'Long Hair' Leung Kwok-hung and district councillors Andrew To Kwun-hang and Tsang Kin-sing, had their permits confiscated during previous attempts to enter the mainland. Since the 1989 Tiananmen crackdown, many pan-democrats in Hong Kong have been barred from crossing the border.
Shouting slogans and displaying a banner, the group took a train to Lo Wu from Hung Hom, accompanied by journalists. On the Hong Kong side of the checkpoint, they read a letter to the standing committee, urging Beijing to heed public demand for universal suffrage by 2012, before crossing the bridge to the mainland side.
The group was immediately led away by dozens of plainclothes officers. All the protesters apart from Mr Lo were sent back to Hong Kong.
Although being followed by plainclothes officers to Shenzhen airport, Mr Lo bought a ticket and left for Beijing on a flight at 2.05pm.
Speaking after returning to the Hong Kong side, Mr Tsang said the mission had already been a partial success as Mr Lo was allowed to continue his journey.
In a similar protest in 2004, pan-democrats were turned away from the mainland side of the Lo Wu checkpoint when Beijing ruled out the introduction of universal suffrage by 2007.