Police arrested a man Wednesday morning who they believe carried out a string of two dozen knifepoint robberies across Long Island and in Queens.

The Nassau County, Floral Park and New York City police departments arrested the suspected robber at Van Siclen Avenue and Jericho Turnpike in Floral Park between 11:30 and 11:45 a.m. after pursuing him for four and a half hours, Floral Park Police Commissioner Stephen McAllister said.

NYPD and Nassau County detectives told McAllister the man in custody is Khalif House, 24, of Hempstead, who has allegedly robbed two dozen stores with a large kitchen knife since March 1.

There is a “high probability that he’s our guy,” McAllister said.

A Nassau County police spokesman could not confirm any details of the arrest, but said officers are “interviewing a person of interest” in connection with the crime pattern, which began at a North New Hyde Park Dunkin’ Donuts.

The search started when a man who lives on North Tyson Avenue in Floral Park saw a  man sleeping on his couch around 7 a.m. Wednesday, McAllister said.

He called Floral Park police and officers who were already nearby responded, McAllister said. House saw them and ran, he said, losing the officers around 7:15 a.m. when he jumped a fence and hid in a cellar door.

The Floral Park officers called NYPD and Nassau County police, who responded with a presence that eventually grew to dozens of officers, two helicopters, and members of multiple task forces, McAllister said. Officers from Nassau County’s K-9 unit, robbery squad and search squad were on the scene, as were NYPD’s fugitive squad and U.S. marshals.

Police set up a perimeter in the area about one-tenth of a mile long and notified the nearby John Lewis Childs School, McAllister said. Nassau County police were ready to deploy 30 more officers when a woman called the Floral Park Police Department saying she had seen a man nearby who matched House’s description, he said.

Police found him and surrounded him after a short chase, McAllister said.

“It was a dogpile,” he said.

Floral Park resident Matt Hynes said NYPD vehicles sped past him as he was driving east on Jericho Turnpike near Tulip Avenue on Wednesday morning. He saw side streets blocked from just past Tulip Avenue to the Holy Spirit Church at South Sixth Street, he said.

The suspect has allegedly robbed 24 stores in Nassau, Suffolk and Queens counties using a large kitchen knife, usually late at night. Nassau police labeled him their top priority in April after he robbed a New Hyde Park Subway shop.

McAllister said House allegedly attempted a 25th robbery at a Dollar Tree store in College Point, Queens, on Tuesday night.

NYPD officers thought he would next head to a Dunkin’ Donuts at Hillside Avenue and Little Neck Parkway because it fit his pattern, McAllister said. They did not find him there but arrested his girlfriend and seized his car, he said.

“We wanted to capture this guy because he’s been a thorn in Nassau County’s side for quite some time with these serial robberies, so it’s a big win for everybody today,” McAllister said.

Most of House’s alleged Nassau County targets have been 7-Eleven, Dunkin’ Donuts, Carvel and Subway stores. Police have said he staked out the locations to make sure no customers were inside, usually wearing a mask or dark cloth to cover his face.

Suffolk County police have participated in the investigation, Nassau police have said.

Floral Park police Sgt. Ron Dagliano was determined to capture House throughout the search Wednesday because cops had him cornered in such a small area.

“He was like a dog with a bone,” McAllister said.