The US military says it is responsible for inadvertently killing 1,139 civilians in its fight against ISIS since August 2014, but many argue they're underestimating.

The report also states that 12 were killed in a May 2017 strike on Mosul.

Other estimates are significantly higher, placing the civilian death toll in the US' fight against ISIS closer to at least 7,000.

The US military says it is responsible for inadvertently killing 1,139 civilians in its fight against ISIS since August 2014, but many argue they're underestimating, according to a report from Defense One's Kevin Baron.

The US Central Command announced internally Sunday that 1,139 civilians have been inadvertently killed in its fight against the Islamic State since August 2014, in 31,406 airstrikes.

The report also states 12 were killed in a May 2017 strike on a Mosul bomb-making facility from a secondary explosion. When the Mosul strike happened in May 2017, BBC reported that 105 civilians were killed.

Estimates from other organizations place the civilian death toll in the Middle East exponentially higher than CentCom estimates.

Airwars, a non-profit organization that tracks civilian deaths in Syria, Libya, and Iraq, estimated that between 7,316–11,637 civilians have been killed in Syria and Iraq by US-led actions.

Read more: Civilian deaths in Afghanistan hit record as suicide attacks surge

Other reports show similar estimates. The Syrian Network for Human Rights estimated in October that 6,395 civilians have been killed in Syria in 2018 alone.

In June, U.S. Army Col. Thomas Veale, a spokesman for the US-led coalition fighting the Islamic State in Iraq and Syria, said no one will ever truly know the number of civilian deaths that have occurred.

“As far as how do we know how many civilians were killed, I am just being honest, no one will ever know,” Veale said in a briefing at the Pentagon by video link from Baghdad. “Anyone who claims they will know is lying, and there’s no possible way.”

US Central Command did not immediately respond to Business Insider's request for comment.