*

Police release suspect photos, offer $10,000 reward for

information

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Security tightened at UnitedHealth ( UNH ), other insurers after

attack

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Shell casings found with words linked to critical

insurance book

(Updates top with 48-hour window closing, link to Breakingviews

column in related items; adds bullet points)

By Rich McKay and Daniel Trotta

NEW YORK, Dec 6 (Reuters) -

The hunt for the killer

of a UnitedHealth ( UNH ) executive passed the crucial

48-hour mark on Friday, as New York police scoured surveillance

video, chased down leads and sought the public's help to find

the gunman.

Brian Thompson

, 50, the CEO of UnitedHealth's ( UNH )

insurance unit

, was shot from behind on Wednesday in what police described

as a targeted attack. Police have released multiple photos of

the suspect, who was last recorded on video riding an electric

bicycle into Central Park after fleeing the scene of the

shooting.

Security experts said the first 48-hours after such a crime

was the best window of opportunity to

catch the gunman

, a timeframe that has now passed.

"The clock is running," said Felipe Rodriguez, a former

NYPD police detective and an adjunct professor at the John Jay

College of Criminal Justice. "They still haven't recovered gun,

the bicycle, the backpack. The longer it takes, they could be

losing vital pieces of evidence."

Rodriguez said solving the case is like putting together a

difficult jigsaw puzzle.

"You start from edges first and work your way in, but right

now they might not have all the pieces. But the case is moving

forward," he said.

Rodriguez added that police must cast a much wider net than

just New York City, because the suspect might have fled the city

or state.

PHOTOS AND CLUES

Police believe the suspect arrived in New York 10 days before

the shooting on a Greyhound bus that originated in Atlanta, and

checked into a Manhattan youth hostel using a fake ID from New

Jersey, several media outlets reported. Reuters has not

independently verified this account.

Police offered a $10,000 reward for information leading to

an arrest and conviction.

UnitedHealth ( UNH ) is the largest U.S. health insurer, providing

benefits to tens of millions of Americans, who pay more for

healthcare than people in any other country. Thompson joined

UnitedHealth ( UNH ) in 2004 and became the CEO of UnitedHealthcare, a

unit of UnitedHealth Group ( UNH ), in April 2021.

Following the attack, UnitedHealth ( UNH ) and several other health

insurers including CVS Health ( CVS ) and Centene ( CNC ) took

down pictures of executives from their corporate websites in an

apparent tightening of security measures.

Centene ( CNC ) said late on Thursday it would no longer hold an

in-person investor day next week, and that the event would be

streamed.

The words "deny," "defend" and "depose" were carved into

shell casings found at the scene, police sources told ABC and

the New York Post. A New York City Police Department

spokesperson would not comment on the report.

The words evoke the title of Jay Feinman's 2010 book

critical of the insurance industry "Delay Deny Defend: Why

Insurance Companies Don't Pay Claims and What You Can Do About

It."

Feinman, a professor emeritus at Rutgers University Law

School, declined to comment.

EXPERIENCED WITH FIREARMS

Detectives believe the perpetrator was experienced with

firearms based on how he slowly and deliberately carried out the

shooting, CNN reported, citing police sources who spoke on the

condition of anonymity because the investigation was ongoing.

Security video showed the shooter, wearing a hooded

sweatshirt, ski mask and a gray backpack, walking up behind

Thompson, raising his handgun and firing at his back. Police

said the gunman arrived outside the hotel several minutes before

Thompson and waited for him to walk past before firing, ignoring

other passers-by.

CNN, whose reporter John Miller is a former NYPD deputy

commissioner, said police found a phone in an alley that the

gunman ran through and also recovered a water bottle the shooter

bought just minutes before the attack.

A fingerprint on the water bottle was too smudged to provide

further clues about the shooter, the New York Times reported,

citing a senior law enforcement official.