The Pentagon had acknowledged on Friday that it was investigating reports that its airstrikes had caused deaths in Mosul. The next phase of the investigation, military officials said, is likely to take about three weeks.
The March 17 airstrikes — which Iraqis said had led to the deaths of possibly 200 people — could have produced among the highest civilian death tolls in an American air mission since the United States invaded Iraq in 2003.
The reports of heavy civilian casualties have come at a critical point in the military campaign to defeat the Islamic State. Iraqi officials said that the Trump administration had appeared to loosen restrictions on the rules of engagement, making it easier for the Iraqis to call in airstrikes. The Iraqis had been frustrated by the Obama administration’s deliberate approach.
