Militer AS sebelumnya mengakui empat helikopter yang jatuh dalam dua pekan terakhir dan menewaskan 20 tentara dan pengawal swasta,   ditembak jatuh oleh kelompok perlawanan.
The US military revealed earlier that four US helicopters which crashed in the past two weeks, killing a total of 20 troops and private security guards, had been shot down by insurgents.