WASHINGTON (Reuters) - A cargo ship hired by the U.S. military fired warning shots at boats suspected to be Iranian, the U.S. Navy said on Friday, underscoring tension in the Gulf as the Pentagon sharpened its warnings to Tehran.
According to American defense officials, the Westward Venture cargo ship chartered by the U.S. Defense Department was traveling in international waters when two unidentified small boats approached on Thursday.
After the boats failed to respond to radio queries and a warning flare, the cargo ship's onboard security team fired "a few bursts" of machine gun and rifle warning shots, according to Cmdr. Lydia Robertson, a spokeswoman for the U.S. Navy's Bahrain-based Fifth Fleet.
"The small boats left the area a short time later," she said by telephone. "They were able to avoid a serious incident by following the procedures that we use."
The news helped push oil prices up more than $3 to $119.50 a barrel -- within striking distance of the record $119.90 hit earlier this week -- as traders worried escalating tensions in the region could eventually disrupt crude shipments.
In Tehran, an Iranian navy source denied that any confrontation had occurred with a U.S. ship in the Gulf. But the source, quoted by a journalist for Iran's state-owned Arabic Al-Alam TV channel, said any shooting that may have occurred could have targeted a non-Iranian vessel.
U.S. defense officials said they suspected the boats were Iranian. "We don't have complete confirmation of that but we suspect it," one official said.
The incident was reported as America's top military officer charged Iran with increasing its support for Iraqi militias with weapons and training used to kill U.S. troops.
Adm. Michael Mullen, chairman of the Joint Chiefs of Staff, Mullen said the United States would continue to rely on diplomatic and economic methods to encourage Iran to change, but stressed the Pentagon had military options.
"When I say I don't want to take any military options off the table, that certainly more than implies that we have military options," Mullen told reporters. "That kind of planning activity has been going on for a long time. I think it will go on for some time into the future."
Tensions in the region have risen this year. In January, the United States said Iranian boats aggressively approached three U.S. Navy battle ships, warning them they would explode in minutes.
In March, another U.S. military-chartered ship preparing to cross the Suez Canal fired warning shots at a small boat, killing an Egyptian on board.
(Reporting by Kristin Roberts and Andrew Gray, Editing by Chris Wilson)