In a newly released image from a surveillance camera, the suspected shooter is smiling at a female hotel employee in New York.
The little flirt between them actually, in a slightly humorous way, provides what is so far the most important clue to identify him, says CNN's intelligence analyst John Miller.
The shooter is believed to have taken a bus from Atlanta to New York, according to sources within the justice system to several American media outlets.
According to information to CNN, the police believe the man arrived in the city on November 24, ten days before the murder, and then checked into a hostel with a fake driver's license.
The CEO of the American insurance company United Healthcare, Brian Thompson, was shot multiple times early on Thursday morning outside a hotel on Manhattan.
Surveillance footage from the scene shows that the perpetrator initially shot Thompson from behind. He was taken to hospital but his life could not be saved.
No one has been arrested yet.
On Thursday, information emerged that the words "Deny", "defend", and "dismiss" were written on the cartridge cases, reminiscent of "Delay, deny, defend" which is the title of a book from 2010. It deals with the tactics insurance companies are alleged to use to avoid paying out premiums.
The investigators are therefore taking a closer look at whether an insurance dispute could be a motive for the murder.
