U.S. airstrikes have reportedly killed 521 Islamic militants and 32 civilians in the past month. According to the Syrian Observatory for Human Rights, 464 militants were members of ISIS and 57 militants belonged to the al Qaeda-affiliated Nusra Front.
The U.S. began its airstrike campaign against ISIS in Iraq in July; the airstrikes were expanded to Syria in September.
The U.S. has been aided in the fight against the Muslim extremist group by Britain and France, as well as Arab allies.
According to U.S. Central Command spokesman Colonel Patrick Ryder, Washington has taken "reports of civilian casualties or damage to civilian facilities seriously and we have a process to investigate each allegation."
Publication date: October 23, 2014