Jeffrey A. Mulcahy, 58, approached the couple in the Kittatinny Point area on the New Jersey side of the river on Sept. 2, 2019 and began talking to them about fishing, U.S. Attorney Craig Carpenito said.
He left and then returned holding a can of beer and acting agitated, the U.S. attorney said.
After the two got out of the water, Mulcahy pulled a pellet gun from his waistband, pointed it at the man and ordered both to the ground, Carpenito said.
He threatened to kill the man, then hit him in the head and neck with the gun, the U.S. attorney said.
Mulcahy pulled a length of rope from his pocket and tried to tie him up, but the man fought back -- tackling Mulcahy and knocking the gun to the ground, Carpenito said.
The man's girlfriend grabbed it and ran to find help as Mulcahy fled.
A little over a half-hour later, an off-duty firefighter spotted Mulcahy's car, called 911 and began following it.
Hackettstown police captured Mulcahy on eastbound Route 46 in Warren County's Independence Township moments later. An officer smelled alcohol on Mulcahy's breath and spotted an open can of Budweiser on the center console, authorities said.
Mulcahy was charged locally before being handed over to federal authorities, who have jurisdiction over the national park.
Mulcahy accepted a deal from the government, pleading guilty Thursday via video conference in federal court in Trenton to assault with a dangerous weapon with the intent to do bodily harm.
U.S. District Judge Michael A. Shipp scheduled sentencing for March 4.
Carpenito credited Hackettstown police, New Jersey State Police and park rangers of the U.S. National Park Service with the arrest and investigation leading to Mulcahy’s guilty plea, secured by Assistant U.S. Attorney Nicholas P. Grippo, the deputy chief of his Criminal Division in Newark.
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