A Houthi militant attack on a Liberian-flagged cargo ship in the Red Sea killed at least two crew members and left the vessel without propulsion in the latest sign that the Tehran-backed group is once again escalating its maritime assaults in the vital trade route.

A Liberian delegation confirmed the deaths during a meeting of the International Maritime Organization. The Associated Press reported that three mariners had been killed, citing the European Union naval force.

¡°The vessel has sustained significant damage and has lost all propulsion,¡± the U.K. Maritime Trade Operations (UKMTO), a liaison between the U.K. Navy and commercial shipping, said on Tuesday. The Greek-owned vessel had sustained hours of attacks, including by propelled grenades and an approach by multiple boats, the group said.