This story has been updated.
The Coast Guard has launched an investigation after a tugboat submerged in the Hudson River near the Tappan Zee Bridge Thursday afternoon.
The Potomac tugboat was tied to a construction barge and hit a cable under the Tappan Zee Bridge shortly after noon. Both people aboard the boat escaped safely by the time emergency responders arrived.
No one was hurt. It is unclear what caused the boat to sink.
Nyack volunteer firefighters responded first in a fire boat. Members of the Piermont dive team also responded as did the Rockland County Sheriff's Department.
They found the 47-foot tugboat was submerged in nine-feet of water.
The boat was carrying up to 1,500 gallons of fuel. It did not immediately appear that any of the fuel leaked into the river.
It is the second crash involving a tugboat at the bridge construction site in three months.
"This incident is very troubling," said Rockland County Executive Ed Day. "We expect a full investigation into the causes of this crash. We want assurances that all safety precautions are being taken as the new Tappan Zee Bridge is built."
The boat is owned by Tappan Zee Constructors, a consortium of companies building the new bridge.
The U.S. Coast Guard is the lead agency in the investigation. The Coast Guard is asking anyone with information or anyone who witnessed the crash to contact them at 718-354-4353.
The Rockland County Sheriff's Department will continue to assist as needed.
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