A US Navy ship encountered a small Iranian high-speed boat in the central Persian Gulf and warned it away by firing a flare, the Pentagon said Friday. Two other similar Iranian boats in the area did not approach as closely. The USS Typhoon tried unsuccessfully to establish radio contact with the Iranian boat after it came within an estimated 180 meters of the Typhoon on Thursday, outside Iranian territorial waters. A Navy official said Friday the ship then fired the flare and continued on its way without incident. The official said there were no signs any of the Iranian boats was armed. Iranian English-language Press TV quoted an unnamed official with the Islamic Revolutionary Guard as denying "any new confrontation" in the Persian Gulf. "The Iranian boats approached the US warship in the Persian Gulf for a routine check," the official was quoted as saying on Press TV. Meanwhile, Iran's Arabic-language Al-Alam TV cited on its Web site an unnamed senior Iranian Navy official as saying that "no accident took place between the Iranian boats and the US ship, but there was a recognition of the US forces' presence in the Persian Gulf." This passed in a "normal way ... and according to protocol, and then the boats left the scene with no accident whatsoever," the Iranian Navy official said. This marked at least the second US Navy encounter with an aggressive Iranian high-speed boat this year. In January, Iranian boats made what the Navy called provocative moves near a US ship in the Strait of Hormuz.