Thousands of Hong Kong people protested on Wednesday against the government's handling of a controversial anti-subversion bill.
Police said 30,000 people took part in Wednesday's protest
Demonstrators staged a candlelit vigil and called for greater democracy, amid mounting criticism of Chief Executive Tung Chee-hwa, who was not directly elected to the post.
In a sign of China's deep concern about the situation, pro-Beijing politicians said a team of middle-ranking mainland officials had arrived in the territory to assess developments.
A BBC correspondent says the officials are reported to have been present at Wednesday night's protest, which saw tens of thousands of people gather outside the territory's legislative council.
The protest followed a 1 July rally when 500,000 people marched to denounce the anti-subversion bill, the biggest protest in the territory since the Tiananmen Square massacre in Beijing in June 1989.
The scale of that protest forced Mr Tung to defer the bill's passage, and no new timetable has been set for it.
Under the Basic Law - Hong Kong's mini-constitution, drawn up on its return to Chinese sovereignty - the territory is required to pass security laws banning treason, sedition, subversion and the theft of state secrets.
But opponents are concerned that China could use the legislation - known as Article 23 - to suppress Hong Kong's political freedom and curb free speech.
Tung Chee-hwa's authority is being questioned
Tsoi Yiu-cheong, a spokesman for the Civil Human Rights Front, said Wednesday's rally was not merely about the bill.
"We will continue to push on our demand until there is
universal suffrage in Hong Kong," he added.
Hong Kong's constitution allows for universal suffrage after 2007, but the government has repeatedly refused to debate the issue.
The Civil Human Rights Front says that the anti-subversion bill should only be discussed when the territory's government is democratically elected, in order to lessen the scope for abuse.
Ahead of Wednesday's rally, Mr Tung promised to listen more closely to public opinion.
"Our goal is clear, it is to win back the support and trust
of the people," he said.
But critics say the rally and Mr Tung's subsequent climb-down on the passage of the anti-subversion bill have seriously undermined
his authority to rule, prompting speculation he may be forced to step down later this year or reshuffle his cabinet.
Appointed by Beijing, Mr Tung has been blamed for a string of policy blunders, including mismanagement of the recent Sars crisis and failing to revive the stagnant economy.
His political difficulties appeared to mount on Wednesday when a key ally - Tsang Yok-sing, leader of the largest pro-Beijing party, the Democratic Alliance for the Betterment of Hong Kong - suggested that Secretary for Security Regina Ip should be removed from her post.
"If Ip continues to handle this legislation she will face some
difficulty," he said.