The United States launched strikes on military targets on Iran’s Kharg Island, a key oil hub, just hours before a deadline set by President Donald Trump, a White House official said Tuesday. The official spoke on condition of anonymity.

The attacks come amid escalating tensions, with Trump warning that a “whole civilization will die tonight” if Iran did not comply with his demands. Earlier in the conflict, the U.S. targeted Kharg Island’s air defenses, radar installations, airport, and hovercraft base, according to satellite analyses by the Institute for the Study of War and the American Enterprise Institute’s Critical Threats Project.

Semiofficial Iranian news agency Mehr reported several explosions on the island but provided no further details.

The strikes coincided with disruptions to Iran’s railway network, which thousands of civilians rely on to flee toward the Turkish border after air travel was suspended due to the war. Israeli military officials also warned citizens to avoid train travel for safety reasons.

Speaking from Budapest, U.S. Vice President JD Vance expressed confidence that Iran would respond to Washington by the 8 p.m. ET deadline, saying the U.S. has already defeated Iran militarily and can inflict greater economic costs than Tehran can impose.