TEHRAN  Iran’s Revolutionary Guard accused the United States on Wednesday of fabricating a video showing Iranian speedboats confronting United States Navy warships in the Persian Gulf over the weekend, according to a report carried by the semiofficial Fars news agency and state-run television.

“Images released by the U.S. Department of Defense about the Navy vessels were made from file pictures, and the audio was fabricated,” an unnamed Revolutionary Guard official said, according to Fars, which has close links to the Revolutionary Guard. It was the first time Iran had commented on the video that the Pentagon released Tuesday.

The audio includes a statement that says, “I am coming to you,” and adds, “You will explode after a few minutes.” The voice was recorded from the internationally recognized channel for ship-to-ship communications, Navy officials have said.

The Pentagon immediately dismissed the assertion that the video, which shows Iranian speedboats maneuvering around and among the Navy warships, had been fabricated. Bryan Whitman, a Pentagon spokesman, said Iran’s “allegation is absurd, factually incorrect and reflects the lack of seriousness with which they take this serious incident.”