– Intensified airstrikes by the U.S.-led coalition have caused a "staggering" loss of civilian life around the Islamic State of Iraq and Syria's stronghold of Raqqa, a United Nations investigator said Wednesday.

A U.S.-backed ground force entered the Syrian city with the help of coalition air raids last week, three years after the area became a hub from which ISIS leaders planned expansion throughout the region and attacks around the world.

Paulo Pinheiro, the chairman of the U.N. Commission of Inquiry on Syria, said Wednesday that coalition airstrikes had now deepened suffering in a city already under the yoke of extremist fighters.

"We note in particular that the intensification of airstrikes, which have paved the ground for an SDF advance in Raqqa, has resulted not only in staggering loss of civilian life, but has also led to 160,000 civilians fleeing their homes and becoming internally displaced," he said.

Human rights and monitoring groups have warned for months of the rising human cost of the coalition's air war in Syria and Iraq as ISIS forces bed in among densely populated civilian areas.

The U.S.-led coalition includes military personnel from dozens of countries, including Britain, France and Australia. According to its latest figures, at least 484 civilians have been unintentionally killed by coalition airstrikes since June 2014. Britain-based tracking group Airwars put that figure eight times higher.

Washington Post