The gunman being sought in the killing of UnitedHealthcare CEO Brian Thompson has not made it easy for the New York Police Department to find him, but he did leave behind some confounding clues that could lead to his arrest, experts said Friday.
Despite firing the fatal shots in a busy part of Manhattan where there are countless security cameras, and despite revealing his face at the hostel where he is believed to have stayed before the fatal shooting, investigators have not yet publicly identified the gunman who ambushed the 50-year-old insurance executive early Wednesday.
Former NYPD Detective Michael Alcazar, who is now an adjunct professor at the John Jay College of Criminal Justice, noted that the time before the shooter's image was widely released has helped him.
"Right off the bat, this guy had a day to get away," Alcazar told NBC News.
"But now that we got his image, I can almost guarantee that detectives have gotten solid leads on who he is from Crime Stoppers or somebody else looking to collect reward money. They probably already have a lot more information about him than they are letting on to the public."
"That might be the lead the NYPD needs," retired NYPD Detective Jillian Snider told MSNBC. "This is someone with distinguishable features. He has a smile."
Earlier, Tom Verni, who is also a retired NYPD detective, told MSNBC's Jose Diaz-Balart that it's only a matter of time before the shooter is identified or arrested now that "his face is being plastered" on news sites across the country. He also didn't rule out that the killer might still be in New York City.
"In a city like New York City you can disappear in a crowd," Verni said.
NYPD Chief of Detectives Joseph Kenny said later they believed the suspect had left New York City. He said they have footage of him entering a cab that took him to a Port Authority bus terminal near 178th Street and Broadway.
“Those buses are interstate buses," Kenny said. "That’s why we believe he may have left New York City.”
Thompson was fatally shot in what Police Commissioner Jessica Tisch said appeared to be a “premeditated, preplanned targeted attack” outside the New York Hilton hotel in midtown Manhattan. He was on his way to speak at UnitedHealth Group’s investor conference when the gunman approached from behind and “fired several rounds,” Tisch said at a news conference after the deadly shooting.
The gunman had been "lying in wait for several minutes" before opening fire, Tisch said.
Thompson's final moments were caught on surveillance camera footage, which showed the gunman approaching him from behind and opening fire. He continued to fire as Thompson fell to the pavement, the video showed.
Police said the shooter arrived at the scene about five minutes before the shooting. Thompson, who lived in Minnesota, was pronounced dead at Mount Sinai West Hospital.
Meanwhile, the shooter fled on foot and then on a rental bike, Tisch said. He was last seen in Central Park.
On Thursday, a possible murder motive emerged when police revealed that shell casings found at the crime scene had the words “deny,” “defend” and “depose” written on them.
UnitedHealthcare has been hit with complaints from thousands of unhappy customers over the years, and Thompson’s wife told NBC News that her late husband had received threats. He was not traveling with a security detail.
Alcazar said payback might be a motive, but several other things also stood out for him when he viewed the video.
"Initially, I thought it might be a guy with a vendetta of some kind and it still may be, given the words that were found on the shell casings," Alcazar said. "But if you look at the video, there is also a confidence there. He shoots. Then when it appears his gun has jammed, he calmly deals with that and starts shooting again."
So, said Alcazar, "if I am working the case I am not ruling out, at least not at this moment, that this could be a hired gun or somebody with a military background who has some experience with weapons."
Alcazar said the fact that no murder weapon has been found might, in and of itself, also be a clue.
"I believe the gun may be specifically a bolt action single shot weapon, which is very specific," he said. "A unique choice of a weapon to execute a target."
But Verni said he is not convinced that Thompson's killer was a pro.
"A professional hitman would have been more of a ghost" and not kill a man on Midtown Manhattan street because even at that hour there are likely to be witnesses, he said.
Also, the fact that the gunman appeared to use "some kind of noise suppressor" on his gun is "kind of odd," he added.
"But he planned this out, that's for sure," Verni said.
Investigators told NBC News earlier that they believe the shooter may have traveled to New York City from Atlanta last month by bus.
Officials are working to see whether they can find a name from the tickets purchased for a Nov. 24 Greyhound trip that might help identify the gunman. Greyhound said it is cooperating with authorities on the investigation.
Police are also looking into whether the gunman paid in cash and used a fake ID to rent a room at a hostel on the Upper West Side of Manhattan, according to two law enforcement officials briefed on the investigation.
Before the shooting, the gunman bought a water bottle and two protein bars from a nearby Starbucks and discarded the items, the sources said.
In addition to the shooting footage, investigators recovered a video showing where the man discarded the purchased items, and police collected them as evidence, hoping it could aid in the investigation, an official said.
"There’s also still a lot of scene crime processing that needs to be done," Alcazar said. "We may know it’s him, but we’ve got to be able to prove it was him and that requires things like collecting and identifying DNA and processing other physical evidence."
