Five American service members were killed when a military aircraft crashed into the Mediterranean during a training exercise, the US European Command (EUCOM) said Sunday.

EUCOM did not specify the type of plane or where it was flying from, but the United States has deployed a carrier strike group to the area as part of efforts to prevent the Israel-Hamas war from spiralling into a regional conflict.

"During a routine air refuelling mission as part of military training, a US military aircraft carrying five service members suffered a mishap and crashed into the Mediterranean Sea. All five of the service members onboard the aircraft were killed," EUCOM said in a statement on the November 10 accident.

Washington rushed military support to Israel and bolstered its forces in the region -- including with the USS Gerald R. Ford aircraft carrier and other warships -- after the Hamas militant group carried out a shock cross-border attack from Gaza on October 7 that Israeli officials say killed about 1,200 people.

Israel's military responded with a relentless air, land and naval assault on Gaza that the territory's health ministry said has left more than 11,000 people dead.