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LONDON, Aug 11 (Reuters) - Britain will crack down on gangs and may call in army support if this week's riots are repeated, Prime Minister David Cameron said on Thursday, saying he would not allow a "culture of fear" to exist on the streets.
The government will also give the police powers to demand people remove face coverings after many looters who ransacked shops during riots in London and other English cities this week wore masks to avoid being identified.
Anyone whose home or business was damaged in the riots, in which four people were killed, may seek compensation under the Riot Damages Act, Cameron said.
"The whole country has been shocked by the most appalling scenes of people looting, violence, vandalising and thieving. It is criminality pure and simple. And there is absolutely no excuse for it," Cameron told parliament, which was called in to emergency session to debate the riots.
Rioters looted shops, set fire to buildings and vehicles and attacked police, harming Britain's image less than a year before London hosts the 2012 Olympics.
"We will not put up with this in our country. We will not allow a culture of fear to exist on our streets. And we will do whatever it takes to restore law and order and to rebuild our communities," Cameron said.
Saying the fightback had begun, Cameron pledged the authorities would hunt down looters and rioters.
"To the lawless minority, the criminals who've taken what they can get. I say this: We will track you down, we will find you, we will charge you, we will punish you. You will pay for what you have done," he said.
Police numbers in London, which have been almost tripled to 16,000 to quell the riots, will remain at that number through the weekend, Cameron said.
He said he would not rule out calling in army support -- an extraordinary event in Britain -- if there were more disturbances.
"It is the government's responsibility to make sure that every future contingency is looked at, including whether there are tasks that the army could undertake that might free up more police for the front line," he said.
Cameron pledged action against street gangs, saying there was evidence they had coordinated attacks on police and looting. The government will make combatting them a national priority, drawing on the success of cities such as Boston in the United States, he said.
He said the government would give the police the power to remove people's face coverings when they were suspected to be involved in crime.
"On dealing with crowds, we are also looking at the use of existing dispersal powers and whether any wider power of curfew is necessary," he said.
Some local authorities already have powers to evict convicted rioters from social housing and Cameron said he wanted to see more local councils doing this.
Calling for action to mend Britain's "broken society", Cameron said the country needed a benefit system that rewarded work, more discipline in schools and action to deal with disruptive families.
Reporting by Adrian Croft, Matt Falloon, Mohammed Abbas, editing by Myra MacDonald