New York prosecutors filed a murder charge against the suspect in the UnitedHealthcare CEO killing, according to court records.

Officials at an Altoona, Pa., news conference on Monday night confirmed 26-year-old Luigi Mangione is a “suspect” in the Midtown Manhattan killing of UnitedHealthcare CEO Brian Thompson.

Mangione was ordered to be held without bail after a brief court appearance in Pennsylvania on Monday night.

NYPD previously said they were holding a man for questioning in Altoona on Monday. The man has a similar gun to the one used in the murder of Thompson. NYPD reportedly sent detectives to Altoona earlier in the day Monday.

Mangione was stopped in Pennsylvania with a fake ID, police sources told ABC News. Altoona police recovered a fake New Jersey driver’s license, a computer and a gun.

He reportedly walked into a McDonalds, where someone recognized him from the photos police have put out. One of his fake IDs matches the one he gave the hostel in New York.

Court papers say Mangione began shaking when police asked if he had been in New York recently.

Local law enforcement reportedly told NYPD that Mangione looked like the shooting suspect. He is currently charged with weapons, forgery, and other charges in Pennsylvania.

This comes on the sixth day of the search for the suspect, which has also extended to Georgia.

As the search continued, UnitedHealthcare increased security measures at its homebase in Minnetonka, as fences went up to barricade part of the building and the parking garage this past weekend.

“Our hope is that today’s apprehension brings some relief to Brian’s family, friends, colleagues and the many others affected by this unspeakable tragedy,” a spokesperson for UnitedHealthcare said in a prepared statement. “We thank law enforcement and will continue to work with them on this investigation.We ask that everyone respect the family’s privacy as they mourn.”

As of this time, a motive hasn’t been determined, but they are focused on clues that suggest a disgruntled employee or angry client of UnitedHealthcare.

“Before long, these guys usually talk — this is not a criminal mastermind,” said James Fitzgerald, a retired FBI profiler, about the case.

Fitzgerald is one of the agents who helped catch the Unabomber, Ted Kaczynski, who terrorized the nation for nearly 20 years, before being caught in 1996.

Fitzgerald explained the tactics investigators could use in their interview in this case—including detectives will learn as much as they can ahead of questioning the suspect. “Normal interview tactics, rapport building, a little bit of praise in there,” Fitzgerald said. “I think this guy is going to come across and tell what he has to tell.”

ABC News also reports that police say they haven’t uncovered evidence that would show the killing had anything to do with Thompson’s private life.

The words “deny,” “defend,” and “depose” were found on the shell casings. The FBI believes the shooter is sending a message linked to ways insurance companies avoid paying medical claims.

Mangione’s family released the following statement Monday night.

“Unfortunately, we cannot comment on news reports regarding Luigi Mangione. We only know what we have read in the media. Our family is shocked and devastated by Luigi’s arrest. We offer our prayers to the family of Brian Thompson and we ask people to pray for all involved. We are devastated by this news.”

On Sunday, divers with the New York Police Department (NYPD) searched a pond in Cental Park for a second day in a row for the weapon and bike. The pond is by the spot police found the suspect’s backpack, which contained a jacket and Monopoly money.

Police also believe they found DNA.

On Saturday, police released two photos of Mangione from a taxi camera, and NYPD detectives arrived in Atlanta looking for clues. Authorities believe the suspect took a bus from Atlanta to New York City, and 34 minutes after the shooting, he left the city by bus.

“That’s really quick. We have him on a bus out of Upper Manhattan. If he takes it to any different spot and gets on another bus, that has to be tracked as well,” said Robert Boyce, the former Chief of Detectives at the NYPD and a contributor to ABC News.

On Friday, the Medica campus in Minnetonka also closed, and a spokesperson said it was “a precautionary measure due to the threat of violence against health insurers.”

Additionally, UCare says its offices will be closed out of caution this week after the agency “received a concerning comment in a phone call” last Friday.

A spokesperson for the organization, which offers Medicaid, Medicare as well as health plans, says employees will be working from home.

Although the call was reported to police, UCare says they aren’t aware of any threat to the offices or team members.

“It’s not a perfect comfort by any means because it actually brings up the sorrow and the wound again,” Mayor Ron Case, Eden Prairie, said in response to the suspect’s arrest.

Case worked at United Healthcare for over a decade and is now retired.

He said Thompson’s reputation made waves in the corporate world.

“Just a really beloved, well-respected colleague and one of those leaders that people describe as insanely smart and really kind to others,” Case said.

In the wake of Thompson’s death, health insurance in the U.S. is in the spotlight.

Case explained education is important.

“It is complicated. People are angry. I get it,” Case said. “I think we all need to be better educated and better informed about how the whole process works, and the role that the federal and state governments play in really mandating how health care looks here in America.”

You can find complete coverage of the investigation by CLICKING HERE.

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The Associated Press contributed to this article.