The Navy's top commander in the Pacific says he's retiring after being passed over for potential promotion to lead all U.S. forces in the region.

U.S. Pacific Fleet commander Adm. Scott Swift said in a statement Monday he's been told he won't be the Navy's nominee to succeed Adm. Harry Harris at Pacific Command, which oversees all branches of the military.

Swift was leading the Pacific Fleet when Navy ships were recently involved in two separate deadly collisions with other vessels.

The USS John S. McCain and an oil tanker collided near Singapore last month, leaving 10 U.S. sailors dead. Seven sailors died in June when the USS Fitzgerald and a container ship collided off Japan.

Harris took over Pacific Command in May 2015. The command oversees U.S. forces in a geographic area from California to India.