The NYPD has released 2 new photos of the man wanted in the killing of a UnitedHealthcare executive

The New York Police Department on Saturday released two new photos of the man wanted in the slaying of UnitedHealthcare CEO Brian Thompson.

The photos are the latest in a series by the NYPD of the same person wanted for questioning in Wednesday’s murder.

A person can be seen in one of the photos in a split of what appears to be a New York City taxi, wearing a blue medical mask and a black hoodie.

Another photo, taken from the car, shows a man outside the window walking next to the car while wearing a blue mask and a black jacket with a hood over his head.

The NYPD said investigators were able to track his movements through taxis.

As the investigation into Thompson’s slaying and the manhunt for the gunman continued Saturday, three sources familiar with the investigation told NBC News that it is still unclear who is the person of interest.

A combined $60,000 reward is being offered by the FBI, Crime Stoppers and the NYPD for information leading to the gunman’s arrest.

Thompson was shot and killed outside the New York Hilton Midtown hotel on his way to a UnitedHealth Group investor conference Wednesday morning, officials said.

Thompson was shot at least once in the back and once in the right calf. He was not accompanied by security.

“Based on the evidence we have so far, it appears that the victim was targeted,” Joseph Kenny, NYPD chief of detectives, said earlier in the week. “But right now, we don’t know why.”

New York Police Commissioner Jessica Tisch said Wednesday that it was a “planned, premeditated, targeted attack.”

The shells found at the scene were marked with “deny”, “delay” and “remove”, police said.

Police also found a gray backpack in Central Park that the man was said to be carrying at the time of the murder. Officials were looking into whether it was the same fund, two senior law enforcement officials told NBC News.

A cell phone was found by police near the scene, and investigators are trying to use it to learn more about the man’s communications and movements, two sources with knowledge of the investigation said.

Four sources familiar with the investigation told NBC News on Saturday that no gun was found in the backpack. Three sources said there was a jacket in the bag, but it is not yet clear if it was the jacket the gunman was wearing when he opened fire.

Authorities believe the man wanted in connection with the murder may have left the state.

Kenny told reporters that the video shows a man riding a bicycle in Central Park, then taking a taxi to the Port Authority bus station near the George Washington Bridge.

Detectives are looking for more video to determine if he got on the bus from there, and if so which one.

Police believe he may have traveled to New York City from Atlanta last month on a Greyhound bus, three law enforcement officials familiar with the case told NBC News. The bus arrived in New York on November 24, after several stops along the way, they said.

New York officials are looking to find the name used in the Nov. 24 ride, and Atlanta and Greyhound police are assisting in the investigation.

While in New York, the man stayed at a hostel on Manhattan’s Upper West Side, the NYPD said at a press conference Friday. Authorities are working to determine if he paid in cash and used a fake ID to rent a room there.

His roommates at the hostel said he always kept his mask on, even when he was eating, pulling it down to bite it, the NYPD said.

Thompson’s wife, Paulette Thompson, told NBC News on Wednesday that her husband had been receiving threats, but it was unclear what they were.

“There were some threats,” he said. “Actually, I don’t know, lack of information? I don’t know the details. I just know that he said that someone was threatening him.”

This article was originally published on NBCNews.com