The victim has been identified as 63-year-old Paul Amon of Bayville in Ocean County, New Jersey.
One man pulled after the tugboat has survived, according to authorities. He has not been identified.
After striking the barge, the tugboat began leaking up to 5,000 gallons of diesel fuel, creating a fuel slick approximately 100 yards wide and 5 miles long.
A fuel-containing apparatus has been deployed in the Hudson River due to a visible sheen.
Westchester County has initiated a cleanup agreement with a private party, Miller Environmental Group, to manage the diesel spill. Personnel from the State Department of Environment Conservation's Oil Spill Team are on the scene to monitor and support the cleanup with two DEC vessels – one 31 feet with a crew of three and the other 44 feet with a crew of three.
"The Division's Office of Emergency Management and Fire Prevention and Control staff are providing command and control support and will continue to assist local, state and federal first responders during this incident," Division of Homeland Security and Emergency Services Commissioner John P. Melville said.
Emergency crews are continuing their search for two men who remain missing.
State Police Superintendent Joseph A. D'Amico said: "The State Police have been working with our local law enforcement partners as well as first-responders and the U.S. Coast Guard on rescue and recovery efforts since the accident was first reported. Our divers are working now to determine the position of the sunken tug so a decision can be made on how recovery operations will proceed."
The tugboat, which was not involved with the new TZB construction projected, was escorting a barge with a crane and two other tugboats and traveling south toward Jersey City at the time of the accident.
"Saturday morning's deadly tugboat accident near the new Tappan Zee Bridge only highlights the dangerous work of those involved in such a massive construction project," Rockland County Executive Ed Day said. "Our thoughts and prayers are with the victims, their families and the brave first responders involved in the difficult rescue and recovery. As work on the new span continues, we must be assured that an incident like this never happens again."
Gov. Andrew Cuomo called the accident "a tragedy" and said a "full investigation" to understand what led to the crash will be launched.
Tappan Zee Constructors, the builders of the bridge replacement, had a crew of 21 workers on their barge at the time; none were injured when the tugboat struck.
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