Two crew members of the Peruvian Navy’s ship BAP Guise suffered burn injuries this morning when an engine fire broke out on board the ship as its crew participated in the biennial Exercise Rim of The Pacific off Hawaii, the Pervuian Navy confirmed in a statement tonight.

The RIMPAC watch floor received reports of the fire at about 8 a.m., according to a RIMPAC spokesperson. Other vessels assisted the Guise and its crew after the fire broke out.

Two “critically stable” patients were evacuated from the ship by a helicopter from French navy frigate FS Prairial to the U.S. Coast Guard’s Hawaii based cutter CGC Midgett, RIMPAC officials said.

A U.S. Navy helicopter from aircraft carrier USS Abraham Lincoln then picked up the injured Peruvian sailors and brought them to Oahu where they have been hospitalized.

RIMPAC tweeted this afternoon as that of 1:40 p.m. the fire in the engine room aboard the Guise had been extinguished.

The Peruvian Navy statement said no other crew members were injurred and that the families of the injured have been notified. Peruvian officials will “evaluate and present an initial report on the events that occurred, to determine the corresponding actions,” the statement said.

The biennial RIMPAC is the world’s largest recurring naval exercise and this year’s iteration is the largest since it began with five nations in 1971. This year 26 nations are participating in the exercise with 38 surface ships, four submarines, more than 170 aircraft, 30 drones and 25,000 personnel in and around the Hawaiian islands and Southern California from June 29 to Aug. 4.