Report on raids that killed 140 villagers found rules had not been adhered to, official says.

    A failure to follow strict rules devised to prevent civilian casualties in Afghanistan led to the death of scores of villagers last month, a US military investigation has concluded.

    According to a senior military official who spoke to the New York Times, the report on the four May raids found that one plane was cleared to attack Taliban fighters, but then had to circle back and did not reconfirm the target before dropping its payload, leaving open the possibility that the militants had fled or that civilians had entered the target area in the intervening few minutes.

    In another case, a compound where militants were massing for a possible counterattack against US and Afghan troops was struck in violation of rules that required a more imminent threat to justify putting homes at risk, the official said.