Sept. 11 (Bloomberg) -- The U.S. Coast Guard sent gunboats to the Potomac River in Washington today as part of a training exercise on the eighth anniversary of the Sept. 11 attacks, prompting the FBI and other law enforcement agencies that hadn’t received advance notice to race to the scene.

The exercise was conducted about the time President Barack Obama was at a Sept. 11 ceremony at the Pentagon, which required crossing the river on a nearby bridge.

The training prompted media reports of a possible incident on the river, including a report on CNN that shots were fired at another boat. There was no gunfire, though weapons were mounted on the front of several of the Coast Guard boats, said Petty Officer Second Class Nathan Henise.

A top Coast Guard official defended the exercise at a news conference outside the Coast Guard’s Washington headquarters.

What took place was a “low-profile training exercise that goes on every day,” Vice Admiral John Currier said. There was “no reason for specific notification” to other agencies, he said.

Currier and White House press secretary Robert Gibbs faulted the news media for rushing out with reports based on partial information picked up over Coast Guard radio frequencies.

‘Unnecessarily Alarmed’

“If anyone was unnecessarily alarmed, based on erroneous reporting that denoted that shots had been fired, I think everybody is apologetic of that,” Gibbs said. The media has a responsibility “to ensure that we may not get this story first, but we may be the first ones to get it right.”

Currier said other agencies reacted to the media reports, which were based on intercepted radio transmissions. He said it would be routine for Coast Guard officers involved to start their transmission by saying they were conducting a drill.

As part of the exercise, a member of the crew mimicked the sound of fired shots and that voice was heard over the Guard’s special radio frequency, Coast Guard officials said.

“One of the guys went, ‘Bang, bang, bang,’” Henise said.

While the Coast Guard can encrypt frequencies to prevent the public from listening, the training’s radio transmission wasn’t blocked, said Commander Ron LaBrec, a Coast Guard spokesman.

FBI Not Notified

Law enforcement agencies including the Federal Bureau of Investigation and U.S. Park Police sent officers to the river, which forms the western boarder of Washington and passes near the Pentagon and other federal buildings.

“FBI was not notified, and when we heard it on the news we responded the way we would to any incident,” said Katherine Schweit, a spokeswoman for the FBI’s Washington Field Office.

Lieutenant Michael Libby of the Park Police, which has jurisdiction over federal areas on shore, said officers responded to the scene, initially unaware that it was a training exercise.

The Federal Aviation Administration stopped flights from nearby Ronald Reagan Washington National Airport, an FAA spokeswoman said.

“We stopped departures from National Airport from about 10:08 to 10:30,” spokeswoman Diane Spitaliere said. She wouldn’t say how they were informed of the situation, only that it was done “out of an abundance of caution.” She added that the FAA wasn’t told of the exercise beforehand.

The Standard & Poor’s 500 Index erased a gain of 0.4 percent after CNN reported the Coast Guard had fired on a boat. Stocks resumed their advance after the Coast Guard said it was a training exercise.

Market ‘Spooked’

“The market got spooked,” said Edward Craig, head of U.S. equity trading at Jefferies & Co. in New York. “It’s just heightened sensitivity because of the date. Any type of news such as that is going to make the market jump one way or the other. I think it’s a calendar thing rather than anything of substance.”

The unit involved in the exercise has four 25-foot boats with a total of 30 crew members, Coast Guard officials said. LaBrec said he didn’t know if all four boats took part in this morning’s training.

LaBrec, who said he didn’t have the specifics about this particular drill, said typically on such exercises several boats will try to communicate or use other measures to stop another boat that isn’t complying with security restrictions.

The exercise began around 9:30 a.m., he said. The Coast Guard began receiving calls about an incident on the river at 9:40 and confirmed just after 10 a.m. that it was the training exercise, he said.

Flyover Incident

The incident was reminiscent of the April 27 flyover of New York by one of the planes used as Air Force One and a fighter escort. That exercise, involving low-flying jets over New York Harbor, rattled windows and prompted office workers to flee high-rise buildings out of fear it was a repeat of the Sept. 11 attacks.

An Obama administration aide who authorized that flight resigned and the Defense Department said the exercise wasn’t properly reviewed.

Gibbs today said the capital is safer because of training exercises such as the Coast Guard’s and that it wasn’t analogous to the Air Force One training incident.

Lawmakers said they wanted to know more about the decision- marking process at the Coast Guard and its mother agency, the Department of Homeland Security.

“It sounds very much like the left hand didn’t know what the right hand was doing,” said Senator George Voinovich, an Ohio Republican who’s a member of the Senate Homeland Security and Governmental Affairs Committee.

To contact the reporters on this story: Jeff Bliss in Washington at jbliss@bloomberg.net; Justin Blum in Washington at jblum4@bloomberg.net

Last Updated: September 11, 2009 14:49 EDT

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