[Scan-DC] Can you believe this?

[James Richardson]

WASHINGTON (CNN) -- A security incident Friday on the Potomac River was
prompted by a training exercise, two sources in the Washington police
department said the Coast Guard told them.

A source in the FBI also told CNN it was a training exercise. The Coast
Guard told CNN it was looking into the matter.

The U.S. Coast Guard appeared to be trying to prevent a boat from entering a
security zone on the Potomac River not far from the Pentagon, where
President Obama had been at an event commemorating the September 11 attacks.

Police scanner traffic said the Coast Guard vessel had fired shots.