As U.S.-supported rebels advanced on a strategic town held by Islamic State in northern Syria this month, coalition warplanes paved the way with airstrikes.
They targeted what they thought were jihadist positions — but their strikes have resulted in the highest number of civilian casualties since the start of the coalition's campaign against Islamic State, monitoring groups have warned.
One of those airstrikes outside Manbij killed dozens of people Tuesday, activists said.
A number of pro-opposition organizations based in the town reported anywhere from 56 to 212 people were killed in the pre-dawn hours, when airstrikes pounded a string of houses in the villages of Tokhar and Hoshariyeh, roughly 10 miles to the north. The number of casualties could not be independently verified by the Los Angeles Times.
Manbij, a one-time hub for archaeological smuggling 48 miles northeast of Aleppo, is an essential stop on the corridor connecting Aleppo province to Islamic State's de-facto Syrian capital of Raqqa. Its proximity to Syria's northern border makes it an important hub for Islamic State members seeking to move between the group's territories and Turkey.
An estimated 70,000 people are thought to be trapped in the town and its surrounding villages.
Frightened residents had fled to the area as clashes raged between the U.S.-backed Syrian Democratic Forces, a predominantly Kurdish militia operating in northern Syria, and Islamic State militants bunkered there.
"After the first strikes, people rushed to remove the victims, and that's when the planes struck the site once again," the administrator of the "Manbij — Mother of the World" Facebook page said in an interview on Wednesday. Like others interviewed for this article, he would not give his full name for reasons of security.
Another activist, who wished to be identified only as Abu Omar, uploaded pictures depicting the remains of buildings he claimed had been destroyed in Tuesday's attacks, as well as graphic images of dust-covered corpses, including infants.
Amaq News, an agency affiliated with Islamic State, issued a report Tuesday saying 160 civilians were killed in Tokhar as a result of American airstrikes.
Syria's government condemned the airstrikes in letters of complaint issued by its Foreign Ministry to the U.N. and the U.N. Security Council, saying, "Whoever wishes to fight terrorism in a serious matter should coordinate with the government of [Syria] and its army."
Syrian Democratic Forces spokesman Sharfan Darwish insisted that Islamic State had been present in the village and that the death toll was exaggerated.
"We monitored the movements of Daesh. We saw a rocket launcher, a car bomb, a tank … and they had gathered in great number in Tokhar to launch a counterattack against us," he said, using the Arabic acronym for Islamic State.
"Only two houses were hit on the outskirts of the village," he said. "How can 200 civilians be in two houses? The numbers must be inflated."
Another Manbij activist, who gave his name as Hmoud, said the rocket launcher had been placed among civilians.
"When a missile struck the launcher, that explosion caused the most damage."
Yet according to Christopher Woods, head of Airwars, a nonprofit organization that tracks the international air war in Iraq and Syria, Tuesday's strike was "simply the latest in a string of attacks."
"We were already preparing this news story to go out before [the Tokhar attack] because our researchers were so alarmed by the high number of casualty reports relating to Manbij," Woods said in a phone interview Wednesday.
Airwars estimates anywhere from 150 to 165 civilians have been killed since June 10, including a significant number of women and children.
On Wednesday, the coalition released a statement confirming it had conducted airstrikes near Manbij and was "aware of reports alleging civilian casualties in the area." The group said the claims were being investigated and if they warranted further investigation, "[the Coalition] will then determine the next appropriate step."
Earlier, an official release of airstrike information by U.S. Central Command said coalition warplanes had conducted three airstrikes near Manbij, knocking out Islamic State tactical units, fighting positions, a command and control node and vehicles. It did not mention any civilian casualties.
However, coalition spokesman Col. Christopher Garver said in an email Wednesday the "initial assessment" was "still ongoing."
In May, the Syrian Democratic Forces mounted an offensive aimed at ousting the jihadists from the area. On Wednesday, the militants advanced into the southern neighborhoods of Manbij.
The U.S., which has come under criticism for its failure in forging a proxy ground force against Islamic State, has been quick to tout the Syrian Democratic Forces' success, despite complaints that the Kurdish-dominated force intends to assimilate territories under its control into an autonomous Kurdish entity on Syrian soil.
Bulos is a special correspondent.
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