Hong Kong democracy activists on Thursday expressed shock and incredulity after a Chinese official was quoted as saying that the fact they are still "alive" reflects well on Beijing's tolerance.

The remark by China's top official in Hong Kong was said to have been made at a meeting with local pro-democracy lawmakers on August 19, shortly before Beijing dashed their hopes for full and unfettered democracy in the city.

"The fact that you are alive shows the country's civility and inclusiveness," Zhang Xiaoming, the director of China's Liaison Office in Hong Kong, was quoted as saying in Mandarin by three people who attended the closed-door meeting .

"I was astounded," one of the people told AFP, on condition of anonymity, after the blunt comment first emerged in an article Thursday by Reuters news agency.

"He was dead serious, it was no joke," the person said.

Two of the people at the meeting were activists from a group that wants Beijing to reverse its verdict that China's pro-democracy student movement in 1989 was a subversive uprising, another attendee said.

The Chinese army killed hundreds -- by some estimates more than 1,000 -- protesters in the Tiananmen crackdown.

"This topic of whether these activists should be allowed to run for the chief executive spot and if they were considered patriots was being discussed when we heard Zhang say that," the second attendee said.

The Chinese Liaison Office declined to comment on Zhang's remarks.

"It's really very ridiculous for a mainland official to say things like that," Democratic Party chairwoman Emily Lau, who attended a separate meeting with Zhang, told AFP.

"We've been banned from travelling to the mainland for more than two decades so now they say that the fact that you're still alive you should count your blessings. That's just crazy," she said.

Most pro-democracy activists in the southern Chinese city are not allowed to travel to mainland China.

Public discontent has been growing in Hong Kong over increased political interference and the perceived cosy relationship between the city's powerful business elite and Beijing.

A coalition of protest groups has vowed to usher in a new "era of civil disobedience" against Beijing's decision to vet candidates who want to run as Hong Kong's chief executive in 2017.

Hong Kong activists shaved their heads Tuesday in a symbolic act of protest against China's increased political control over the city, which was made clear in the elections ruling issued on August 31.

Britain handed Hong Kong back to China in 1997 under a "one country, two systems" agreement which allows civil liberties not seen on the mainland, including free speech and the right to protest.