A person of interest in the killing of a UnitedHealth executive was arrested after being spotted at a McDonald’s in Pennsylvania following a dayslong manhunt, New York City officials said.

A McDonald’s employee in Altoona, Pa., about 85 miles east of Pittsburgh, saw Luigi Mangione, 26, eating and called police Monday morning, the New York City Police Department said at a news briefing Monday afternoon. He was arrested on firearms charges. Authorities called him a “strong person of interest” in the killing of UnitedHealthcare Chief Executive Brian Thompson.

“A McDonald’s employee did something we ask every American to do: If you see something, say something,” New York City Mayor Eric Adams said.

Police believe Mangione traveled from New York after fatally shooting Thompson early Wednesday outside a Midtown Manhattan hotel before an investor meeting. The suspect wrote the words “delay,” “deny” and “depose” on bullets that are believed to have come from his gun, a law-enforcement official said. Those words are commonly associated with tactics insurers use to avoid paying claims.

Police said Mangione was acting suspiciously and had a firearm suppressor, a ghost gun potentially made with a 3-D printer and clothing and a mask consistent with the suspect’s. He also had a U.S. passport and multiple fraudulent IDs, including a New Jersey ID that matched the one the suspect used to check into a New York City hostel.

Mangione also had a handwritten three-page document that showed “some ill will toward corporate America,” said NYPD Chief of Detectives Joseph Kenny.

The questioning in Pennsylvania comes after days of labor-intensive police work that has included scanning thousands of hours of surveillance footage, interviewing witnesses, tracking down hundreds of tips and gathering evidence for forensic analysis. Police said on Friday they believed the suspect left New York on a bus.

Police said Mangione was born and raised in Maryland and was believed to have attended college in Pennsylvania. He had ties to San Francisco and his last known address was in Honolulu. Police believe he was acting alone and they didn’t have his name before Monday. They don’t believe he was planning to flee the country.

Detectives and prosecutors were heading to Altoona from New York to question Mangione, police said.

“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 UnitedHealth Group spokesman said.

Authorities found surveillance footage showing the suspect entering Central Park on an e-bike after the shooting, taking a taxi up the west side of Manhattan and entering a bus station. Police were offering a reward of up to $10,000 for information leading to an arrest in the case. The FBI was offering up to $50,000 for information leading to the arrest and conviction of the person responsible for the crime.

By Friday, NYPD detectives had pieced together a timeline of the suspect’s movements on the day of the shooting, and his arrival in the city some 10 days earlier. Police had searched a hostel on Manhattan’s Upper West Side on Thursday, where they believe the man might have stayed.

The assailant got to New York City on Nov. 24 just after 10 p.m., police said, on a bus that originated in Atlanta but made several stops along the way.

The morning of the shooting, the suspect was in the area outside the Hilton hotel for nearly 30 minutes, NYPD Chief of Detectives Joseph Kenny told CNN on Friday.

He fled the scene on a bike and rode into Central Park, where investigators believe he might have abandoned a backpack. Officers found a bag there that looked similar days later.

Before the shooting, he visited a Starbucks and made purchases with cash, a law-enforcement official said. Investigators recovered a cellphone in an alley near the shooting.

Thompson was ambushed in what police called a “brazen, targeted attack.” The father of two, who lived in Minnesota, was in the city for an investor meeting. He was heading to the event to help set up when he was shot, police said. Executives cut the event short after the attack.

Thompson’s wife told NBC News that he had received threats potentially linked to issues of healthcare coverage. His killing brought fresh attention to corporate security concerns in the insurance industry. Health-insurance executives said it isn’t unusual for companies and their leaders to be threatened or sued by customers, often over high costs or rejected coverage.