A manhunt has been launched by the New York police to find the attacker who on Wednesday morning killed in cold blood by shooting in the back the CEO of UnitedHealthcare, one of the largest health insurance companies in the USA, Brian Thompson.

The assailant remains at large, but authorities are scrutinizing his steps before and after the attack as they say he may have left some vital clues, according to police officials who spoke to CNN on condition of anonymity.

New York police described the incident as a “brazen, targeted attack” that took place as Brian Thompson walked to the hotel hosting UnitedHealthcare’s annual investor conference.

“Several people passed the suspect, but he appeared to be waiting for his target,” police said at a news conference Wednesday. “I want to be clear: at this point, every indication is that this was a premeditated, pre-planned, targeted attack,” he said.

The gunman approached Thompson from behind and shot him with a silenced weapon at least once in the back and once in the right calf. Although the CEO of UnitedHealthcare was immediately taken to the hospital, he did not make it.

The motive for the attack remains unclear. However, a source with knowledge of the investigation told CNN that UnitedHealthcare’s parent company, UnitedHealth Group, was aware of threats against its high-level executives. The threats, however, did not specifically mention Thompson by name, the source said. Thompson’s widow, Paulette, told NBC News that “there have been some threats” against her husband.

“I don’t know the details. I just know he said there were people threatening him,” the source said.

Brian Thompson’s wife described her husband’s death as “senseless,” according to CNN.

“We are devastated to hear of the senseless killing of our beloved Brian,” said Paulette Thompson.

“Brian was an incredibly loving, generous, talented man who truly lived life to the fullest and touched so many lives. Most importantly, Brian was an incredibly loving father to our two sons and we will miss him dearly,” Paulette added. “We appreciate your wishes and ask for complete privacy as our family experiences this difficult time.”

The video from the cold murder

When the gunman shot Thompson, the UnitedHealthcare CEO was walking to the Hilton for an investor conference, according to security camera footage.

Officials said the gunman got out from behind a car parked on the sidewalk, ignored bystanders and casually shot the victim from behind. The assailant then moved closer to the victim and continued to fire until the gun apparently malfunctioned. The suspect fired again before fleeing through an alley.

New York

“He appears to be knowledgeable in the use of firearms as he was able to resolve malfunctions fairly quickly,” NYPD Chief of Detectives Joe Kenney said at the news conference.

Firearms experts who have studied the video say it appears the gun jammed – preventing him from continuing to fire. After completing his “project” he fled on foot and then on an e-bike, police said.

Investigators told CNN the suspect crossed the street, started running and may have dropped a phone and a water bottle in the alley. Video at a nearby Starbucks shows the gunman buying a bottle of water and two energy bars minutes before the shooting, a senior police official said.

The phone could provide fingerprints, DNA and – if police technicians can unlock the phone – other clues to the suspect’s identity.

The suspect was last seen riding a bicycle in Central Park minutes after the shooting, police said. Investigators have conducted searches in the area. At this time, police have not located the bike or the weapon used, investigators told CNN.

Investigators are also looking into whether the bike was prearranged because they believe the suspect may have taken the subway from the Upper West Side to Midtown, according to law enforcement officials briefed on the investigation.

Police have video of the suspect on the Upper West Side carrying what appears to be an electric bicycle battery, the sources said.

The perpetrator of the attack was released on a $10,000 bond.