New Image Shows Suspect in C.E.O. Shooting in Back of Taxi

The manhunt for the gunman who fatally shot Brian Thompson, chief executive of UnitedHealthcare, entered its fifth day, and the police released two new images.

The Police Department has released two new images of the man it believes fatally shot the chief executive of UnitedHealthcare, including one showing him in the back seat of a taxi on the day of the shooting.

The images were released late Saturday night as the frantic investigation continued to identify and track down the killer of Brian Thompson, 50, the health care executive gunned down outside the New York Hilton Midtown hotel in Manhattan on Wednesday.

One image, captured from the front of the cab, appears to show the unidentified suspect peering forward from the vehicle’s back seat with his face partially obscured by a blue surgical mask, a dark hat and a black hood. The other image, apparently recorded through a window, shows the man walking on the street wearing the same mask, a black puffer jacket and a hood pulled over his head.

The police have said that the man caught a taxi around 7 a.m. Wednesday on the Upper West Side, about 15 minutes after he shot Mr. Thompson. He took the cab uptown to a bus terminal near the George Washington Bridge, where they believe he may have caught a bus out of the state.

Though the killing set off a manhunt that stretched well beyond New York City and commanded days of national attention, the man remained at large on Sunday, and the police were still searching for information about who he was and what had motivated him to shoot Mr. Thompson.

The taxi images are the latest to emerge as the police scour thousands of hours of footage from surveillance cameras around the city to glean information about the man’s movements on the day of the killing. They also recovered bullet casings at the scene with the words “depose,” “deny” and “delay” written on them — a possible reference to terms used by insurers to avoid paying claims.