"I’m being hired by the British government to consult with them on the issue of gangs from the American experience and to offer some advice and counsel on their experience"

British Prime Minister David Cameron, under attack over his leadership during the rioting and looting that swept English cities this week, has enlisted U.S. street crime expert William Bratton to advise the government on handling gang violence, Reuters reported.

"I'm being hired by the British government to consult with them on the issue of gangs, gang violence and gang intervention from the American experience and to offer some advice and counsel on their experience," Bratton told Reuters in New York.

British police flooded the streets again on Friday night to ensure weekend drinking does not reignite the rioting that shocked Britons and sullied the country's image a year before it hosts the Olympic Games.

Steve Kavanagh, deputy assistant commissioner of the Metropolitan Police, said 16,000 officers, instead of the usual 2,500, would remain on duty in London in their biggest peacetime deployment -- a measure of the perceived public order challenge.

Other forces, including those in Nottingham, Birmingham and Liverpool, said they would maintain a high level of policing over the weekend, though they said they did not expect further trouble after a couple of nights of quiet.

Cameron, describing the four nights of looting said the initial police response had been inadequate. His remarks drew a sharp reaction from the police service, which is facing deep cuts in numbers as part of a government austerity drive aimed at cutting the large public debt.

More than 1,200 people were brutally arrested during and after the unrest. Some police forces have taken unusual steps to crack down on the protesters and deter future violence.

Iran's Foreign Ministry on Friday summoned British charge d'affaires in Tehran over the continuing use of violence by police against protesters and called on the British government to “heed the demands and true requests” of protesters.

The trouble began in London after police shot dead a black man and refused to give his relatives information about the incident, but then degenerated into widespread looting and violence in many parts of the capital and other major cities.