Gen. Joseph Votel, head of U.S. Central Command, testifies on Yemen and other issues related to the Middle East before the Senate Armed Services Committee. (Win Mcnamee/Getty Images)

A U.S. military investigation has determined that an American-led raid in Yemen killed up to a dozen civilians, a senior official said Thursday, the most specific admission yet that the January operation resulted in unintended loss of life.

Gen. Joseph Votel, who heads U.S. Central Command (Centcom), told lawmakers that a probe into the Jan. 29 raid had concluded that between four and 12 civilians died as a result of U.S. actions.

Military officials had previously said that noncombatants “were likely killed.” Yemeni reports have put the civilian death toll as high as about 30.

The raid, which also resulted in the death of a Navy SEAL, has become the object of intense scrutiny early in the Trump administration. While the White House has insisted its first major counterterrorism operation was a highly successful maneuver against al-Qaeda in the Arabian Peninsula (AQAP), critics have questioned the series of mishaps that befell the Special Operations forces on the ground.

Some within the U.S. government have also cast doubt on the value of the intelligence obtained in the operation, which targeted a remote village believed to be inhabited by AQAP militants.

According to Yemeni security and tribal officials, an intense firefight and U.S. air attacks were elements of a chaotic nighttime scene in which villagers not connected to AQAP sought to defend their homes and became caught up in the fight. They allege that a large number of women and children were among the dead.

Votel, speaking before the Senate Armed Services Committee, provided no details of who those killed were believed to include but said that, as the Centcom commander, he took responsibility for what occurred.

“We lost a lot on this operation,” he said. “We lost a valued operator; we had people wounded; we caused civilian casualties; lost an expensive aircraft.”

Maj. Josh Jacques, a Centcom spokesman, said it was not clear whether further information from the investigation would be made public. While Centcom has a system to investigate claims of civilian deaths, its probes often find much smaller civilian death tolls than those identified by activists and advocacy groups.

Votel said that a separate investigation into the crash and scuttling of an Osprey tilt-rotor aircraft during the operation was continuing. But he said an after-action review had not found any indication of negligence or poor decision-making that would require yet another investigation that could lead to recommendations for disciplinary action.

“I think we had a good understanding of exactly what happened . . . and we’ve been able to pull lessons learned out of that we will apply in future operations,” Votel said.