Five of the six soldiers killed in the deadliest single attack on British forces in Afghanistan since 2001 were aged 21 or under, the Ministry of Defence said on Thursday. The men, who had reportedly been in the country for less than a month, died when a massive explosion ripped through their armoured vehicle during a patrol on Tuesday near the city of Lashkar Gah in Helmand Province, southern Afghanistan. Taliban insurgents on Thursday claimed responsibility for the attack, saying they had used a land mine. The deaths pushed the number of British dead since the 2001 invasion of Afghanistan over the 400-mark, to 404. The youngest victim was 19-year-old Private Christopher Kershaw while three others were 20 and one was 21.