Three Indian sailors were killed in a U.S. airstrike on the Palau-flagged tanker Settebello, which Washington said violated its blockade on Iranian oil exports.

The U.S. military stated that it targeted the vessel’s engine room after the crew repeatedly ignored instructions from American forces.

India confirmed the deaths, lodged a strong protest with the U.S., and summoned the U.S. deputy chief of mission.

The incident marks the first reported fatalities linked to the blockade, which began on April 13 and has sharply reduced Iranian oil exports, Yahoo News has reported.

The strike comes amid rising tensions between the U.S. and Iran, with renewed military exchanges, threats to shipping in the Strait of Hormuz, and concerns over global energy supply disruptions.