HK tense as police bring in rubber bullets

Hong Kong authorities have urged demonstrators outside the chief executive's office and the government and police headquarters to calmly disperse.

Hong Kong protesters confront police outside the legislative government complex on Oct 2, 2014, calling for open elections and the resignation of Chief Executive Leung Chun-ying. (Paula Bronstein/Getty)

Tensions in Hong Kong are rising after police were seen unloading boxes of tear gas and rubber bullets close to the city's besieged government headquarters as the authorities urged pro-democracy demonstrators to disperse "as soon as possible".

Protesters have shut down central areas of the southern Chinese city with a mass sit-in, including outside the city's legislative assembly, and have given Chief Executive Leung Chun-ying until midnight to step down, or face escalated action.

China backed the city's embattled leader saying it was behind Leung "firmly and unshakably" and pledged support for the police as protesters prepared for a fifth night on the barricades.

In days of peaceful demonstrations tens of thousands of people have taken over the city's usually traffic-heavy streets as they demand Beijing grant fully free elections in the semi-autonomous city.

Last month China said Hong Kongers would be able to vote for their next leader in 2017 but only those vetted by a loyalist committee would be allowed to stand - something demonstrators have dismissed as a "fake democracy".

The city authorities on Thursday said they wanted the streets cleared around the government headquarters with more than 3000 civil servants expected to return to the headquarters after a two-day public holiday.

In a statement, officials called on protesters "not to block the access there and to disperse peacefully as soon as possible".

Classes in the protest-affected areas will also be suspended on Friday, they added.

The late afternoon resupply by police officers caused widespread alarm among protesters as their leaders issuing fresh calls for people to swell their ranks.

Pictures shared widely on social media and television showed one barrel with the words "Round, 38mm rubber baton multi" written on it.

Another had "1.5 in, CS" emblazoned on it, a possible reference to CS gas.

"I am worried that the police will use force to disperse the movement tonight," Andrew Shum, a member of Occupy Central, one of the main protest groups, said.

"Everyone is discussing what they are going to do next."