washington u.s.-led coalition fight islamic state militants say thursday another 51 civilians kill strike iraq syria raise total number civilians kill 786 since 2014. coalition say statement september assess 127 report 51 additional deaths occur 16 incidents go back far february deem credible coalition battle defeat islamic state militants iraq syria say go great lengths avoid civilian casualties military official tally far outside organizations monitor group airwars say least 5,637 civilians kill coalition strike iraqi force launch attack drive islamic state last territory hold iraq thursday syrian army ally say plan march jihadists last syrian stronghold separate assault across iraqi-syrian frontier aim deal final blow islamic state caliphate crumble year syria iraq group lose cities mosul raqqa swathe territory u.s.-led force acknowledge kill 51 civilians iraq syria