A couple enjoying a Labor Day swim at the idyllic Delaware Water Gap slipped into a nightmarish scene from a thriller when a strangertried to kidnap them at gunpoint, authorities said.

The couple managed to fight off the assailant — although not without injury — and call for help.

After a high-speed chase through parts of Warren County, police arrested and charged Jeffrey Mulcahy, 57, who is now facing federal charges.

Mulcahy, a Wayne resident, is being held in federal detention until he is placed at a treatment facility while he awaits trial.

The attack happened at the Kittatinny Point area of the Delaware Water Gap in Warren County, according to a federal criminal affidavit filed by a U.S. park ranger. LehighValleyLive.com, citing the National Park Service, identified the victims as a male and female couple.

The affidavit says a man, later identified as Mulcahy, approached the couple while they were swimming and began talking to them about fishing. He left after a while and returned 15 minutes laters, appearing "agitated," they told police.

The victims told rangers that Mulcahy pulled out what appeared to be a handgun — later identified as a pellet gun — and pointed it at the woman's head, ordering both to get on the ground.

The victims told investigators that Mulcahy threatened to kill the woman if her boyfriend did not follow his commands. The gunman beat the man in his head and neck and then took out a rope to try to tie the man's hands behind his back.

The victim, however, resisted and wrestled the assailant, who dropped his gun. The man's girlfriend grabbed the gun and ran off to call 911, officials said.

After the attacker took off and the man went to find his girlfriend, he said he saw Mulcahy drive by in a white van, whose license plate number he memorized, the affidavit says.

Police in Warren County were told to be on the look out for the vehicle just after 5 p.m.

An off-duty firefighter traveling on Route 46 in Independence radioed county dispatchers to let them know that he was behind the white van.

A Hackettstown cop spotted the van and tried to pull over the driver, who police said ignored the lights and sirens and continued to drive.

Police said Mulcahy threw a bloody T-shirt out of the window of the moving van before stopping on the highway.

Police said Mulcahy smelled of alcohol and the cop noticed an open can of Budweiser in the center console.

He was arrested and turned over to federal authorities.

He's facing local charges of third-degree eluding, hindering, disorderly conduct, failure to wear seatbelt, driving while intoxicated, refusal to submit to breath test, possession of an open container of alcohol in a motor vehicle, throwing debris from motor vehicle, failure to maintain lane, failure to pull over for a motor vehicle, reckless driving and speeding.

Sergio Bichao is deputy digital editor at New Jersey 101.5. Send him news tips: Call 609-359-5348 or email sergio.bichao@townsquaremedia.com.

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