REPORT: The First Month Of US Airstrikes In Syria Killed Over 500 Militants - And 32 Civilians

Beirut (AFP) - Air strikes by the US-led coalition in Syria have killed 553 people since their launch a month ago, the vast majority of them jihadists, a monitoring group said on Thursday.

The strikes have killed 464 Islamic State group fighters, 57 militants from Al-Qaeda affiliate al-Nusra Front and 32 civilians, the Britain-based Syrian Observatory for Human Rights said.

Among the civilians killed were six children and five women, said the Observatory, which relies on a wide network of sources inside Syria.

The US-led coalition against the Islamic State launched air strikes against IS on September 23, expanding a previous aerial campaign launched against the group in Iraq in August.

Observatory director Rami Abdel Rahman told AFP the "vast majority" of jihadists killed in the strikes were not Syrians but foreign fighters who had joined IS and Nusra in the country.

On October 16, US Central Command spokesman Curtis Kellog told Business Insider that the US military had no knowledge of its operations in either Iraq or Syria causing civilian deaths.

"We continue to have no operational reporting or intelligence indicating US or coalition airstrikes have caused civilian casualties in Iraq or Syria," Kellog told Business Insider by email.

The US-led coalition has focused most of its efforts in Syria around preventing ISIS from taking Kobane, a Kurdish city on Syria's border with Turkey. The campaign has succeeded in stanching the jihadists' advance on the city, with one Kurdish fighter claiming that ISIS only controlled around 5% Kobane on October 21.

Business Insider has reached out to both CENTCOM and the Syrian Observatory for comment.