WASHINGTON (AP) — The Pentagon knew there were survivors after a September attack on an alleged drug boat in the Caribbean Sea and the U.S. military still carried out a follow-up strike, according to two people familiar with the matter.

The rationale for the second strike was that it was needed to sink the vessel, according to the people familiar with the matter who spoke on the condition of anonymity because they weren’t authorized to discuss it publicly. The Trump administration says all 11 people aboard were killed.

What remains unclear was who ordered the strikes and whether Defense Secretary Pete Hegseth was involved, one of the people said. That will be part of a classified congressional briefing Thursday with the commander that the Trump administration says ordered the second strike, Adm. Frank “Mitch” Bradley.

Hegseth has defended the second strike as emerging in the “fog of war,” saying he didn’t see any survivors but also “didn’t stick around” for the rest of the mission.

Hegseth is under growing scrutiny over the military strikes on alleged drug traffickers in the Caribbean and eastern Pacific. Legal experts and some lawmakers say a strike that killed survivors would have violated the laws of armed conflict.