WASHINGTON (Reuters) - The top U.S. commander in Iraq on Tuesday acknowledged the likelihood that the U.S.-led coalition had a role in blasts in Mosul that killed civilians this month but said an investigation was underway and that Islamic State may also be to blame.

“My initial assessment is that we probably had a role in these casualties. Now, here’s what I don’t know. What I don’t know is were they (the civilians) gathered there by the enemy? We still have some assessments to do,” Lieutenant General Steve Townsend told a Pentagon news briefing, speaking from Iraq.

“I would say this, that it sure looks like they were.”

Conflicting accounts have emerged since the March 17 explosion in al-Jadida district in west Mosul, where Iraqi forces backed by U.S.-led coalition air strikes are fighting to clear Islamic State militants from Iraq’s second city.

Investigators are in Mosul to determine whether a U.S.-led coalition strike or Islamic State-rigged explosives caused a blast that destroyed buildings and may have killed more than 200 people.

“My initial impression is the enemy had a hand in this. And there’s also a fair chance that our strike had some role in it,” Townsend said. “I think it’s probably going to play out to be some sort of combination. But you know what, I can’t really say for sure and we just have to let the investigation play out.”