LONDON (AFP) - Britains riots claimed a fifth life Friday with the death of a man who confronted looters during the worst unrest in decades, as a row erupted between police and politicians over the disturbances. A huge police presence and heavy rain prevented fresh violence Thursday, but the death of a 68-year-old man attacked by a mob at the height of the violence in London led to police launching a murder investigation. Richard Mannington Bowes was set upon Monday in the affluent London suburb of Ealing, which experienced some of the worst violence during the four nights of rioting, as he attempted to stamp out a fire started by a gang of youths. He died in hospital late Thursday, the fifth fatality after the deaths of three men in Birmingham who were run over as they defended local businesses, and the fatal shooting of a man in Croydon, south London. The attack on Mannington Bowes was a brutal incident that resulted in the senseless killing of an innocent man, said Detective Chief Inspector John McFarlane of Londons Metropolitan Police. Police arrested a 22-year-old man over the murder on Friday. Inquests were due to open later into the deaths in Birmingham, which saw three young men of South Asian origin mown down by a car as they stood guard against looters outside a petrol station. Meanwhile, British Prime Minister David Cameron unveiled measures to end the countrys worst riots in decades, and admitted the army could be called in to quell the violence which claimed its fifth fatality on Friday. Cameron told an emergency session of parliament he would give police extra powers including the ability to order youths to remove face coverings. Cameron said that a year before London hosts the 2012 Olympics, Britain needed to show a more positive face to the world after the riots in which dozens of buildings have been torched. We will not stop until this mindless violence and thuggery is defeated and law and order is fully restored on all our streets, he told lawmakers. We need to show the world, which has looked on frankly appalled, that the perpetrators of the violence we have seen on our streets are not in any way representative of our country nor of our young people. On the political front, a row escalated between police and politicians as both sides sought to deflect blame for the crisis. Some have criticised polices reluctance to crack down hard on the first riot in the north London district of Tottenham on Saturday, saying the cautious approach encouraged unrest to continue and spread across the country. The number of officers on the streets of London was boosted from 6,000 to 16,000 after the unrest escalated and the same number of officers remained on the streets of the capital on Thursday. In an emergency session of parliament Thursday, Prime Minister David Cameron said police would be given extra powers to prevent future trouble but also voiced criticism. Initially the police treated the situation too much as a public order issue rather than essentially one of crime, he told lawmakers. Home Secretary Theresa May later added her voice to the criticism, saying there were not enough officers on duty on Monday, the worst night of the unrest during which police in London arrested more than 300 people. But senior officer Hugh Orde, who represents Britains police chiefs, hit back, saying that frontline officers had performed magnificently and dismissing intervention by political leaders as an irrelevance. The police faced an unprecedented situation not just in London but across the country, he told BBC TV. The force responded magnificently and the officers put huge effort into protecting communities and more importantly protecting life. He criticised a claim by May that she had ordered police forces across the country to cancel all staff leave, saying that she has no power whatsoever to order the cancellation of police leave. Despite media criticism that many of the rampaging youths came from broken homes with absent parents, there was growing evidence Friday that adults were willing to report their own children to the police over the riots. In Manchester, an angry mother marched her 15-year-old son down to the local police station after she recognised him among rioters prising open the shutters of a shop on Tuesday, police said. He was arrested on suspicion of looting. Meanwhile Malaysian student Asyraf Haziq Rosli, 20, who has become a symbol of the violence after he was mugged by a group of youths who pretended to help him after he suffered a broken jaw, said he was determined to stay in Britain despite the attack. My family are worried about me and my mother would like me to go home. But I am determined to stay, he said, adding he still thought Britain was great. Footage of his ordeal has been watched by millions of people on the Internet. Police arrested a man over the robbery.