* Security tight in Hong Kong
* Legislative meeting adjourned on Thursday
* Thousands of protesters ready to step up demonstrations
* Government offices to close for the rest of week
* Some bank services suspended, staff work from home (Updates number of protesters, details of tension)
By Clare Jim and Sumeet Chatterjee
HONG KONG, June 13 (Reuters) - Thousands of protesters readied in Hong Kong on Thursday for more potential clashes with police over a planned extradition law with mainland China, a day after police fired tear gas and rubber bullets at unarmed demonstrators.
Small scuffles broke out between police and demonstrators around the city's legislature, the epicentre of the violence, while some protesters rushed to stop police from removing supplies of face masks and food.
Uniformed police with helmets and shields blocked overhead walkways, while a long row of police vans was parked nearby. Plainclothes police officers checked commuters' identity papers.
Schoolchildren joined the steadily growing crowd, which swelled to a few thousand by midday, from around 20 early in the day.
"We are ready to have a protracted war with the government," said one protester, Natalie Wong. "I am young, that's why I have to fight for Hong Kong."
The extradition bill, which will cover Hong Kong residents and foreign and Chinese nationals living or travelling through the city, has sparked concerns it may threaten the rule of law that underpins Hong Kong's international financial status.
The legislature remained closed, with the council issuing a notice that the group's meeting would not be held on Thursday.
Authorities have shut government offices in the financial district for the rest of the week after some of the worst violence in Hong Kong since Britain handed it back to Chinese rule in 1997.
On Wednesday, police fired rubber bullets, tear gas and pepper spray in a series of skirmishes to clear demonstrators from the legislature, with officials saying 72 people had been admitted to hospital by 10 p.m.
It was the third night of violence since a protest on Sunday drew what organisers said was more than a million people in the biggest street demonstration since the 1997 handover.
Several thousand demonstrators stayed until the early hours of morning near the legislature in the Admiralty district, while thousands more retreated to the Central business district, overlooked by the towers of some of Asia's biggest firms and hotel chains, including HSBC and AIA.
Hong Kong's benchmark stock exchange slid as much as 1.5 percent on Thursday, extending losses from the previous day.
Most roads around the business district were opening for traffic, but Pacific Place, a prime shopping mall next to the legislature, stayed shut.
Banks, including Standard Chartered, Bank of China and DBS, said they had suspended branch services in the area.
Banks in the Central district emphasised it was ‘business as usual' but many offered staff the option of working from home.
"As a precaution, we shut two outlets early where the protests were taking place. Our priorities are the safety of our employees and supporting our customers," said HSBC, whose ground-level public space at its headquarters has previously been a focal point for protests.
Hong Kong's China-backed Chief Executive Carrie Lam condemned the violence late on Wednesday and urged a swift restoration of order.
While acknowledging the controversy, Lam has refused to postpone or withdraw the bill, which she and her officials say is necessary to plug "loopholes" that allow the city to be a haven for criminals wanted on the mainland.
Lam has said the courts would provide human rights safeguards in vetting case-by-case extraditions to mainland China.
Opponents, including leading lawyers and rights groups, say China's justice system is marked by torture and forced confessions, arbitrary detention and poor access to lawyers.
In an impromptu media standup in the legislature, democratic lawmakers strongly criticised Lam's heavy-handed police response.
"We are not a haven for criminals, but we have become a haven of violent police. Firing at our children? None of the former chief executives dared to do that," said legislator Fernando Cheung.
"But 'mother Carrie Lam' did it. What kind of mother is she? I have never seen such an evil-hearted mother."
In editorials on Thursday, Chinese state media said the protests were "hammering" Hong Kong's reputation.
"It is lawlessness that will hurt Hong Kong, not the proposed amendments to its fugitive law," said the English-language China Daily.
CONCERNS OVER MORE UNREST
Face masks, goggles, helmets and water bottles strewn around the legislature area were being cleaned up, while a police team stood nearby, looking relaxed.
The adjacent Admiralty metro station remained shut while commuters crowded into other stations, with some diverted into sprawling bus queues.
Concern over the unrest prompted Hong Kong's Tourism Board to call off its dragon boat carnival this weekend and index provider MSCI to cancel a Thursday conference at a hotel near the skirmishes.
The city's Bar Association expressed concern over video footage of police using force against largely unarmed protesters.
"In these cases the police may well have overstepped their lawful powers in maintaining public order," it said in a statement.
Amnesty International joined domestic rights groups in condemning Wednesday's use of police force as excessive, while a spokeswoman for the U.N. Human Rights Office in Geneva said it was following the situation closely.
"We call on all parties to express their views peacefully and on Hong Kong's authorities to engage in an inclusive and transparent dialogue over the draft legislation," the spokeswoman said.
Diplomatic pressure was also building after leaders such as British Prime Minister Theresa May and U.S. President Donald Trump commented on the protests.
The European Union said it shared many Hong Kong citizens' concerns over the proposed extradition reforms and urged an in-depth public consultation.
"This is a sensitive issue, with potentially far-reaching consequences for Hong Kong and its people, for EU and foreign citizens, as well as for business confidence," it said in a statement. (Reporting by Julie Zhu, Sumeet Chatterjee, Clare Jim, Jennifer Hughes, Anne Marie Roantree, James Pomfret, Alun John, Vimvang Tong, Jessie Pang and Felix Tam; Additional reporting by David Stanway in SHANGHAI; Writing by Farah Master and Greg Torode in HONG KONG, Editing by Michael Perry and Clarence Fernandez)
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