The Pentagon has struggled in recent weeks to explain what lies behind a surge in reported civilian casualties in its air campaign against the Islamic State, fueling speculation that the new Trump administration is pursuing policies resulting in a greater loss of life.

Military officials insist there has been no significant change to the rules governing its air campaign in Iraq and Syria, and instead attribute the string of alleged deadly incidents to a new, more intense phase of the war, in which Islamic State fighters are making a final stand in densely populated areas such as the Iraqi city of Mosul.

But some in Iraq and Syria are left wondering whether the higher death count is a product of President Trump’s bare-knuckle military stance and his suggestions that the United States should “take out” militants’ families.

The recent incidents, and the attention surrounding them, have generated concern within the military that the strikes have undermined the United States’ ability to fight the Islamic State.

“It does have a negative impact on our image at least throughout the region and the world, and it’s probably detrimental to the strength of our coalition. And that’s exactly what ISIS is trying to target right now,” Col. Joseph Scrocca, a military spokesman, said in a recent media briefing. ISIS is an acronym for the Islamic State.

The military’s difficulty in accounting for the civilian casualties – exacerbated by classified regulations and a complex process for airstrikes – has allowed the Islamic State to advance its own version of the events.

The Islamic State has recently accused the United States of killing hundreds of residents of Mosul and decried what it has said are “continuous American-Iraqi massacres” in that city and elsewhere.

“We’re ceding space to the adversary, who wants to create the perception of disregard for civilian life,” said David Deptula, a retired Air Force general who heads the Mitchell Institute for Aerospace Studies.

Incidents that have been brought up by rights groups include a March 17 strike on a crowded building in Mosul that may have killed at least 140 people.

Another strike on March 16 was in the vicinity of a Syrian mosque. Both attacks are under investigation.

The surge in reported casualties in March was so dramatic that it prompted Airwars, a respected watchdog group, to suspend its tracking of Russian air operations in Syria – known to take a devastating toll on civilians – to focus on U.S. actions.

Since U.S. jets dropped their first bombs on the Islamic State in 2014, U.S. military leaders have called the air war in Iraq and Syria the most meticulous ever in avoiding unnecessary loss of life.

But the Pentagon has scrambled to address questions about the recent spike in civilian casualties.

That difficulty was apparent last month when, in the space of three days, senior military officials gave conflicting accounts about basic aspects of the air campaign.