The U.S. military says the drone shot down by Iran overnight was the Navy version of the RQ-4A Global Hawk High-Altitude Long Endurance Unmanned Aircraft, built by Northrop Grumman Corp. at a cost of $130 million a plane.

“U.S. Central Command can confirm that a U.S. Navy Broad Area Maritime aircraft was shot down by an Iranian surface-to-air missile system while operating in international airspace over the Strait of Hormuz,” Navy Capt. Bill Urban, a CENTCOM spokesman, said in a statement Thursday morning.

“Iranian reports that the aircraft was over Iran are false. This was an unprovoked attack on a U.S. surveillance asset in international airspace,” said Urban.

The commander of Iran’s Islamic Revolutionary Guard Corps says the country shot down a U.S. drone to send “a clear message” to America. In a speech carried live on Iranian state television, Gen. Hossein Salami said Iran does “not have any intention for war with any country, but we are ready for war.”

The RQ-4 Global Hawk is the largest drone in the U.S. inventory, described in an Air Force fact sheet as “a high-altitude, long-endurance, remotely piloted aircraft” capable of flying more than 30 hours at a stretch.

The attack comes less than 24 hours after Secretary of State Mike Pompeo blamed Iran for the increase in tensions and tweeted , “President @realDonaldTrump does not want war with Iran. We will continue to communicate that message, while doing the things that are necessary to protect American interests in the region.”

President Trump has not yet commented on the drone incident, but seemed to brush off the prospect of war late Wednesday at the end of a long phone interview with Fox News host Sean Hannity. Asked by Hannity about his vow not to allow Iran to acquire nuclear weapons, Trump said simply, “We'll see what happens. I would say if I were you, don't worry about a thing.”

Sen. Lindsey Graham, R-S.C., who is no longer on the Armed Services Committee but still has the president's ear, had said Wednesday the situation is “getting more dangerous by the day." In an interview with Bret Baier on Fox News, Graham said it may soon be time to send Iran an unambiguous message.

“My red line is if there's any more disruption of shipping in the Straits of Hormuz linked to Iran, take out their Navy, bomb their refineries. If there's any more attacks on American interests, go after the Iranians so they'll pay pain. They'll feel pain,” he said.

Democrats in Congress are expressing increasing alarm that the Trump administration might use the authority granted after the Sept. 11 attacks to justify the use of force against Iran.

At a House Foreign Affairs Committee hearing yesterday, Brian Hook, the U.S. special envoy for Iran, refused to state whether only Congress has the authority to wage war with Iran, saying the question would be better answered by a lawyer.

“This is something which the Office of the Legal Adviser can give you an opinion on,” he said, while adding, “If the use of military force is necessary to defend U.S. national security interests, we will do everything that we are required to do with respect to congressional war powers and we will comply with the law.”

“Military action against Iran without the approval of Congress is absolutely not an option,” Foreign Affairs Chairman Eliot Engel, D-N.Y., said during the subcommittee hearing.

Sen. Ted Cruz, R-Texas, told the Washington Examiner that he has no doubt Trump has the authority to retaliate directly against Iran if regime-controlled forces kill any Americans. “As retaliation for a strike on U.S. troops, absolutely,” he said.

“The president, as commander in chief, has constitutional authority to defend those troops and to respond to such an attack,” Cruz said. “On the other end of the spectrum — for large-scale, extended military conflict — that takes authorization from Congress.”