NYPD releases new photos while gathering evidence in hunt for gunman who shot UnitedHealthcare CEO 

As the search for the gunman who is accused of fatally shooting UnitedHealthcare CEO Brian Thompson in midtown Manhattan entered a fourth day Saturday, police are relying on extensive surveillance footage to piece together his movements while he was in the city.

On Saturday, an NYPD official said investigators found a Tommy Hilfiger jacket inside the Peak Design backpack they located Friday in Central Park, which they believe belonged to the shooting suspect.   

The investigation has stretched beyond city limits as authorities said they have “reason to believe” the suspected shooter left New York City by bus Wednesday. 

Police have not identified the suspect but released two new photos Saturday of the person wanted for questioning in the case. One shows a man inside what appears to be a cab.

The FBI is offering a reward of up to $50,000 for information leading to an arrest, urging anyone with information to contact its tip line at 1-800-225-5324 or the New York City Police Department's tip line at 1-800-577-8477. Tipsters can also submit information at tips.fbi.gov.

In a briefing with reporters on Friday, NYPD Chief of Detectives Joseph Kenny provided a more exact timeline of the suspect's actions in the shooting of Thompson outside a Hilton hotel on Sixth Avenue Wednesday.

The timeline was constructed after an extensive examination of surveillance video evidence done by scores of NYPD video team members.

Here are some key moments:

The gunman arrived in New York 10 days before the shooting.

Police said the suspect arrived on Sunday, Nov. 24, at the Port Authority bus terminal in Manhattan shortly after 10 p.m. The bus originated in Atlanta, but it made a number of stops along the way, so police are in contact with authorities at those locations.

He then took a cab uptown to the vicinity of the midtown Hilton at 54th Street and Sixth Avenue and stayed in the area for about 30 minutes, according to police. Around 11 p.m., he took a taxi to the HI New York City Hostel on Amsterdam Avenue.

He stayed at a hostel on the Upper West Side.

The man checked into the hostel and stayed for five days, checking out briefly on Friday, Nov. 29, and checking back in Nov. 30 in what police described as an administrative checkout.

He reportedly had two roommates at the hostel and remained masked virtually all the time, save for an interaction at the front desk of the hostel. An image of the suspect with his mask down and smiling has been released by police.

Police said there's no evidence he stayed overnight anywhere else, and they believe he booked the room using fraudulent identification and paid in cash.

The suspect traveled by bicycle on the morning of the shooting.

Investigators believe the suspected gunman left the hostel on a bike at 5:30 a.m. Wednesday, arriving at 54th Street and 6th Avenue and wandering around by 5:41. He is seen going into a Starbucks.

An hour later, at 6:44, the masked gunman approached Thompson from behind and opened fire on a sidewalk outside the Hilton hotel. Thompson, 50, of Maple Grove, Minnesota, was in New York for an annual investors meeting of UnitedHealth Group, the parent company of UnitedHealthcare. 

At 6:48 a.m., police said, the suspect entered Central Park at 60th Street and Center Drive on a bike. He emerged at Central Park West at 6:56 a.m. and is seen two minutes later at 85th Street and Columbus Avenue with the bike.

At 7 a.m., the man is seen walking north at 86th Street without the bike. Police on Saturday had not recovered the bike or the gun used in the shooting, an NYPD official said.

Police haven't identified the suspect.

Authorities have not released the suspect's identity in what police have called a targeted, brazen assassination.

Detectives are looking into whether the gunman used a veterinary gun used to euthanize animals on farms and ranches, Kenny said. Such guns are advertised as being quieter when shot than other weapons.

Investigators also found apparent messages — the words "delay," "deny" and "depose" — from the shooter on shell casings found at the scene, a law enforcement source has told Newsday. The words echo a 2010 book entitled "Delay, Deny, Defend: Why Insurance Companies Don't Pay Claims and What You Can Do About It" by Jay M. Feinman.

His whereabouts are still unknown.

At 86th Street and Amsterdam Avenue, the suspect is seen entering a cab at 7:04 a.m. and reappears on surveillance footage near the Port Authority bus station near the George Washington Bridge at 7:30

Police are still determining what bus route he may have taken out of the city and are trying to track his movements out of state.

Police are also testing a discarded Starbucks coffee cup and wrapper for possible fingerprints and DNA, Newsday previously reported.

A water bottle was also tested, Kenny said, adding that fingerprints found so far have not been of evidentiary value.