WASHINGTON (Reuters) - The top U.S. general in Iraq told reporters on Tuesday that a strike near the Islamic-State-held Syrian city of Raqqa last week appears to have killed dozens of militants and not civilians.

Last week the Syrian Observatory for Human Rights said an air strike that hit a school sheltering displaced people killed at least 33 people, adding it believed the strike was carried out by the U.S.-led coalition fighting Islamic State in the area.

“I would tell you that we haven’t completed our assessment of that event yet, but my initial read is (it is) not credible,” Lieutenant General Stephen Townsend told reporters at a Pentagon via teleconference.

“I think that was a clean strike,” Townsend said.

“We had multiple corroborating intelligence sources from various types of intelligence that told us the enemy was using that school and we observed it and we saw what we expected to see,” Townsend said, adding that it appeared to have hit about 30 Islamic State militants.