KABUL (Reuters/AFP) - An Afghan who has spent over six years at the US militarys Guantanamo Bay prison was only around 12-years-old when he was detained, not 16 or 17 as his official record says, an Afghan rights group said on Tuesday. Interviews with the family of Mohammed Jawad, who like many poor Afghans does not know his exact age or birthday, showed he was probably not even a teenager when he was arrested in 2002, the Afghan Independent Human Rights Commission (AIHRC) said. He was picked up by Afghan police in connection with a grenade attack in Kabul in which two US soldiers and their Afghan interpreter were wounded. He was transferred to US custody the same day and flown to Guantanamo in early 2003. Commissioner Nader Nadery said in addition to being a minor at the time of his detention, Jawad was tortured and abused by the Afghan police and while at the Guantanamo detention centre, located at a US naval base in Cuba. The Commission is seeking his release and repatriation, and in the course of looking into his case found out he was probably considerably younger than his records showed. In its findings, which the commission released Tuesday, into the disputed casualty toll from US airstrikes this month, it said up to 97 civilians, most of them children, may have been killed. It said insurgents involved in the May 4-5 fighting in the southwestern province of Farah had knowingly put civilians at risk but the military had also reacted with too much force. This comes after an Afghan government investigation found that 140 civilians died in the strikes against insurgents, making it one of the deadliest such incidents since the US-led invasion in 2001. A US military investigation has disputed the toll, saying 20-30 civilians may have been killed as well as 60-65 Taliban. The commission said it had sent three investigators to Bala Buluk district a few days after the fighting and they had interviewed witnesses, community elders and aid workers. AIHRC believes that as many as 97 persons may have been killed in the air strikes, the vast majority civilians, it said in a statement. Available records suggest that 21 were women and 65 were children, 31 of whom were girls and 34 boys, it said. Witnesses and other sources reported that the 11 other adult males reported killed in these three compounds were also civilians. Locals had told the commission that between 25 and 30 insurgents were also killed but it was not clear if they died in initial fighting or in the air strikes, the rights watchdog said. AIHRC said the hours-long incident had started when 300 insurgents had attacked a series of police checkposts along a key road with the aim of taking control of the route so they could extract tax from any opium traffic. Air bombardments began on two villages in the evening but there were conflicting reports about whether the insurgents were even present at the time, the commission said. During the bombardment, three houses where civilians had taken shelter were hit, the statement said. The commission said it was continuing its investigation, including into US allegations that the insurgents had used the civilians as shields. At a minimum, reports from the villagers suggest that (the insurgents) knowingly, if not deliberately, place civilians at high risk of attack, it said. Nonetheless, AIHRC believes that the level of force used by pro-government forces, particularly in the follow-up airstrikes, was disproportionate. It was also a cause of concern that bombs were even dropped in a populated area, it said. The commission meanwhile raised doubts about the government investigation, saying it appeared to have been conducted in haste. Thirty-nine percent of the deaths were attributable to pro-government forces, of which nearly two-thirds were from air strikes, it said.