NEW ORLEANS (AP) — After an intense 24-hour manhunt, New Orleans police Sunday arrested a man believed to have shot and killed a police officer while wearing handcuffs as he was being transported to jail.

But questions remain about where the gun he used to kill Officer Daryle Holloway, 45, came from and how he hid from a law enforcement search that included canine, SWAT and helicopter teams.

Travis Boys, 33, was still wearing his broken handcuffs when a rookie officer and his trainer spotted him trying to board a city bus Sunday morning, said Police Superintendent Michael Harrison.

“To my understanding, he got on the bus after spotting the officers. And the officers saw that and then he got off the bus and then was apprehended,” Harrison told reporters, while standing in front of a memorial to the city’s fallen police officers.

Authorities took Boys to a hospital for treatment of apparent dehydration, Harrison said. Video by WDSU-TV showed Boys strapped onto a gurney and being put into an ambulance, his head slumped over.

He will be booked with first-degree murder of a police officer, aggravated escape and illegal possession of a firearm, as well as the aggravated battery charge for which he was originally arrested on Friday night, Harrison said.

Harrison said authorities are investigating how he got the gun that was used to shoot the officer. The officer’s gun was in his holster and not used, Harrison said.

Authorities recovered two weapons in the police vehicle — a .38-caliber revolver that had been used in the initial aggravated battery for which Boys had been arrested and a .40-caliber Smith and Wesson that was used to shoot the officer, Harrison said.

Boys was frisked before being transported, so authorities are trying to figure out where the gun came from, Harrison said.

“We realize that’s an obvious issue. So there are safety concerns, procedural concerns between training and internal investigations we’re going to find out how that happened to ensure that that absolutely never happens again,” Harrison said.

The city was the scene of an intense manhunt Saturday, as rifle-toting police in bullet-proof vests, some with trained canines, searched for Boys, checking backyards and crawl spaces under houses.

Helicopters assisting in the search circled overhead.

At one point, Harrison said, officers Saturday located Boys in a stolen truck and gave chase. When the vehicle crashed into a house in the St. Roch neighborhood, they pursued him on foot but an intense search including police dogs failed to find him, Harrison said.

“We don’t know how he was able to elude us, but we were relentless,” he said, describing Boys as someone who “has become proficient at evading law enforcement.”

Other people are believed to have been with Boys in the vehicle when it crashed, Harrison said. It’s not clear whether he got help breaking his handcuffs.

Holloway, 45, had been a member of the New Orleans Police Department since 1992.

After the shooting Saturday his vehicle careened into an electric pole. Emergency medical personnel called to the scene transported him to the hospital where he later died.

Mayor Mitch Landrieu, who spoke to reporters Sunday along with Harrison, described the officer’s killing as a “despicable and cowardly act.”

“He was more than a great cop. He was a good man. He was a good father. Our hearts break for him and his children on Father’s Day,” he said.

Harrison said Holloway joined the department a year after he himself did so.

“Until yesterday, he was a guy who was full of life. He told jokes … You couldn’t be around him for more than a minute or two and he would become your friend,” said Harrison.

Harrison said Saturday that he met with two of Holloway’s three children and Holloway’s former wife at the hospital after he died. “As a new chief, it was the hardest thing I’ve ever had to do in my life,” said Harrison, who became chief last year.

The last New Orleans Police Department officer killed in the line of duty was Officer Rodney Thomas on July 7, 2013, according to police spokesman Tyler Gamble.

More recently, a Housing Authority police officer, James Bennett Jr., 45, was found shot to death in his patrol car.

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