ARLINGTON, Va., July 20 (UPI) -- U.S. military officials are looking into claims that an American-led airstrike targeting militants in a terrorist stronghold in northern Syria this week haphazardly killed dozens of civilians.
"The destruction of [terrorist] targets in Syria and Iraq further limits the group's ability to project terror and conduct operations," military officials said in a news release.
Officials said three separate airstrikes were conducted on three different militant tactical units in the Manbij area -- a stronghold for the Islamic State terror group, also known regionally by the acronyms ISIS and ISIL.
"On July 19, coalition military forces continued to attack ISIL terrorists in Syria and Iraq," the U.S. military news release said. "In Syria, coalition military forces conducted three strikes using bomber and fighter aircraft against ISIL targets."
The strikes, officials said, "destroyed nine ISIL fighting positions, an ISIL command and control node, and 12 ISIL vehicles."
However, at least two human rights organizations have claimed the U.S.-led airstrikes killed dozens of civilians -- at least 50, and perhaps more than 100.
The Syrian Observatory for Human Rights claimed in a report that 56 civilians were killed -- including 11 children under the age of 18.
"The massacre also resulted in the injury of tens of others, some of them are in dangerous situations," the SOHR report said.
The Turkey-based Syrian Institute for Justice put the civilian toll at least least 85, saying bodies were still being recovered. In total, eight families in the area may have been wiped out by the strikes, the monitoring group said.
Activists on the ground in Syria claimed on Facebook that the civilian death toll exceeded 150.
The claims of mass civilian casualties have since gotten the attention of the American military, The Washington Post reported Wednesday.
"If the information supporting this allegation is determined to be credible, we will then determine the next appropriate step," the U.S. military said in a statement Wednesday, adding that its forces routinely take "all measures during the targeting process to avoid or minimize civilian casualties."
If true, the claims would represent one of the deadliest incidents yet involving Syrian civilians and U.S. or coalition strikes.
Syrian Institute for Justice/Facebook
Tuesday's strategic assaults occurred near the target of another coalition strike on July 5, which the military said destroyed five militant positions. Such airstrikes by the Syrian Democratic Forces (SDF), a coalition group of Kurdish, Arab and U.S. forces, have been commonplace in the area over the last seven weeks as they try to wrest the Manbij area from Islamic State control.
The Post report cited a U.S. statement that said 18 coalition airstrikes had been carried out in the Manbij area between Monday and Tuesday.
SOHR, based in London, claimed in a previous report on Monday that more than 100 civilians, including nearly three dozen children, have been killed in coalition airstrikes near Manbij -- which is located about 40 miles northeast of Aleppo near Syria's border with Turkey -- since May 31.
U.S. officials said in a report earlier this month that 36 civilians had been killed in American-led strikes in Syria over the last 12 months. If the claims of new civilian casualties are true, they would more than double -- or triple -- that figure.
"[Locals] are now full of hatred for the SDF. We thought they were coming to finish ISIS, but it seems they are finishing us first," Jassem al-Sayed, an opposition council member who governed in Manbij before the Islamic State's takeover, told the Post.