New photos have been released showing a person of interest in the investigation into the murder of United Healthcare chief executive Brian Thompson.
They show a person wearing a hoodie and surgical mask inside a taxi and then outside the vehicle.
Mr Thompson was shot dead out the front of a Manhattan hotel on Wednesday, as the senior executive was arriving to attend a conference.
Investigators from the NYPD have repeatedly said they believe the shooting was targeted.
His death has sparked debate around the role of private insurance companies in the United States' healthcare system.
Over the weekend, police divers were seen searching a pond in Central Park, where the killer fled on an e-bike after the shooting.
NYPD chief of detectives Joseph Kenny said the person of interest was spotted at a bus station 45 minutes after Mr Thompson's death.
On Friday evening, investigators found a backpack in Central Park that had been worn by the gunman, police said.
They did not immediately reveal what, if anything, it contained but said it would be tested and analysed.
The FBI announced late Friday that it was offering a US$50,000 ($70,000) reward for information leading to an arrest and conviction, adding to a reward of up to $US10,000 that the NYPD has offered.
The shooter paid cash at the hostel, presented what police believe was a fake ID and is believed to have paid cash for taxi rides and other transactions.
He didn't speak to others at the hostel and almost always kept his face covered with a mask, only lowering it while eating.
The Associated Press reported police have been unable to identify the man using facial recognition technology nor through a fingerprint left on an item he purchased at Starbucks.
On Saturday, New York mayor Eric Adams said police were close to identifying the suspect.
"The net is tightening," Mr Adams said.
ABC/AP