Iran’s deputy foreign minister Abbas Araghchi denied on Friday any military drone was lost recently and suggested the U.S. instead could have downed its own “by mistake.”

The Iranian military said all its drones had returned safely to their bases and denied there was any confrontation with a U.S. vessel the previous day.

“We have not lost any drone in the Strait of Hormuz nor anywhere else,” tweeted Deputy Foreign Minister Abbas Araghchi, adding: “I am worried that USS Boxer has shot down their own UAS by mistake!”

We have not lost any drone in the Strait of Hormuz nor anywhere else. I am worried that USS Boxer has shot down their own UAS by mistake! — Seyed Abbas Araghchi (@araghchi) July 19, 2019

Earlier on Thursday, Trump said the USS Boxer took defensive action after an Iranian drone closed to within 1,000 yards of the warship and ignored multiple calls to stand down.

Trump blamed Iran for a “provocative and hostile” action and said the warship responded in self-defense.

I want to apprise everyone of an incident in the Strait of Hormuz today, involving #USSBoxer, a U.S. Navy amphibious assault ship. The BOXER took defensive action against an Iranian drone…. pic.twitter.com/Zql6nAUGxF — Donald J. Trump (@realDonaldTrump) July 18, 2019

Tehran’s top diplomat, Mohammad Javad Zarif, told reporters Thursday he had “no information about losing a drone today,” as he arrived at the United Nations headquarters in New York.

In Tehran, the semi-official Tasnim news agency also denied the confrontation took place.

It quoted military spokesman Gen. Abolfazl Shekari as saying that “all Iranian drones that are in the Persian Gulf and the Strait of Hormuz, including the one which the U.S. president mentioned, after carrying out scheduled identification and control missions, have returned to their bases.”

Earlier Thursday, Iran said the Revolutionary Guard seized a foreign oil tanker and its crew of 12 for allegedly smuggling fuel out of the country, and hours later released video showing the vessel to be a United Arab Emirates-based ship that had vanished in Iranian waters over the weekend.