A former commander of the USS John S. McCain pleaded guilty Friday to dereliction of duty when the destroyer collided with a commercial tanker, killing 10 sailors and injuring five in the Straits of Singapore last August.

Cmdr. Alfredo Sanchez, who has served in the Navy for more than 20 years, testified during a special court-martial at the Washington Navy Yard, Stars and Stripes reported.

“I am ultimately responsible and stand accountable,” Sanchez said. “I will forever question my decisions that contributed to this tragic event.”

Per disciplinary proceedings, Sanchez agreed to retire from service, forfeit $6,000 in wages, and was issued a letter of reprimand.

Sanchez claimed responsibility for the deadly collision. He said had failed to put a well-rested, well-trained crew in place to steer the destroyer into the Straits. – READ MORE