The U.S. military is investigating reports that it killed a civilian in a recent strike in northwest Syria that meant to target a senior al-Qaida leader, a military official said in a statement Tuesday.

Relatives and neighbors of a 60-year-old man killed in the May 3 strike in the village of Qorqanya, a rural area in northern Idlib province, told The Associated Press that he was a farmer who raised sheep, chickens and cattle and had no involvement with armed groups.

In an initial statement released the day of the strike, U.S. Central Command, or CENTCOM, said its forces had “conducted a unilateral strike … targeting a senior Al Qaeda leader.” It did not provide any further details.

Maj. John Moore, a CENTCOM spokesperson, said Tuesday that U.S. forces “are in the process of confirming the identity of the individual killed in the strike.”

“We are aware of the allegations of a civilian casualty and the outcome of the confirmation process will inform if further investigation is necessary and how it should proceed,” he said.

The local civil defense group in northwest Syria, known as the White Helmets, said in a statement that it had responded to the site after hearing sounds of an explosion and found that a drone strike had killed 60-year-old Lutfi Hassan Masto, a local resident who was tending his sheep at the time. Three of the animals were also killed, the statement said.

Masto’s brother, Mohamed Masto, told The Associated Press that reports that his brother was involved in al-Qaida were “absolute lies” and that his killing was “an injustice and an aggression.”

“He had nothing to do with the revolution. … He had nothing to do with the Al-Nusra Front or with the Islamic State” or any of the other armed groups involved in Syria’s 12-year-old uprising-turned-civil-war, Masto said.

Fayad Jamil Raji, a neighbor, said he had known Lufti Masto — or “Abu Hassan,” a nickname meaning “father of Hassan” — for many years.

“The man was a civilian. He had a farm with poultry, cows and sheep,” he said.

Moore said that CENTCOM’s missions are “meticulously planned and executed to maximize success and minimize the risk of collateral damage and harm to civilians.”

On any given day there are at least 900 U.S. forces in Syria, along with an undisclosed number of contractors, who partner with the Kurdish-led Syrian Democratic Forces. They are tasked with preventing a comeback by the Islamic State group, which swept through Iraq and Syria in 2014, taking control of large swaths of territory, and sometimes also target other militant groups.

In April, CENTCOM reported it had taken part in 35 missions in Iraq and Syria, killing 13 alleged IS operatives and detaining 28.

(AP)