Maritime officials reported that three crew members are missing and 21 others were rescued after an oil tanker came under attack off the coast of Oman.

Maritime security firms suggested the incident may be linked to U.S. operations connected to the blockade of Iranian ports.

The attack reportedly caused a fire in the vessel’s engine room, prompting an emergency response by the Royal Navy of Oman.

U.S. Central Command has not issued an official statement on the incident.