Search-and-rescue operations for a missing U.S. Marine off the Philippine coast have covered more than 6,700 square nautical miles over the course of two days since the Marine was reported missing.

The Marine was part of the 13th Marine Expeditionary Unit on the USS Essex, an amphibious assault ship. He was reported missing at 9:40 a.m. local time on Thursday following “routine operations” in the Sulu Sea,” according to a statement.