A retired New York City Police Department (NYPD) lieutenant and former NYPD commander sheds light on the manhunt for the suspect who shot and killed UnitedHealthcare CEO Brian Thompson and what investigators are doing to track him down.

“He’s not a professional, but he’s calculated. He obviously planned this very well. He planned his escape route, he planned everything beforehand,” Joe Cardinale told Fox News Digital.

Cardinale added that the fact that the killer left the bullets behind and left messages like “cancellation” on them makes him suspect it could be someone involved in, or at least connected to, a civil lawsuit with UnitedHealthcare , meaning this is not a coincidence or “wrong place.” “wrong time” situation.

The words “deny,” “depose” and “defend” were written on the live cartridges and shell casings that the assassin left behind after the shooting.

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The words could be from “Delay. Deny. Defend: Why Insurance Companies Don’t Pay Claims and What You Can Do About It,” a book published in 2010 by Jay Feinman. Fox News Digital was unable to reach Feinman or the book’s publisher, Delden Press, for comment.

“I’m still not convinced it’s someone who happened to be with him that morning. I believe he knew exactly where Mr. Thompson would be at that hour. How did he come up with this?” Knowledge? That’s the big million-dollar question right now,” Cardinale said. “He leaves these clues, he discards it, he planned it from the beginning.”

Cardinale said he had seen such actions by former criminals who he said were arrogant and felt they were “smarter than the police.”

“They want to commit the perfect crime, but they do things to let them know it’s me. I mean, when he showed his face, he had to know there was a camera there and he was showing his face. Maybe “That was just for that flirty moment they were discussing. But I even said that’s someone I would like to talk to because she actually had a conversation with him, the employee at the hostel,” Cardinale said when talking about the person she’s interested in , his face showed in a lobby in a Manhattan hostel.

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Thompson’s wife, Paulette, also said her husband had received death threats.

“There had been some threats,” Thompson’s wife said NBC News“Basically, I don’t know, a lack of (health) insurance? I don’t know any details. All I know is that he said there were some people who threatened him.”

When asked why the NYPD is not releasing the name of the individual in question, Cardinale responded that the public needs to know and that there are certain elements of this case that they do not need to know at this time.

“They give as much as they can without jeopardizing a case that, once caught, must move forward and secure a conviction. “So, just to get it out to the public, you can’t screw up their case before it’s even formed,” Cardinale said.

He added that the authorities know that the person in question is watching and listening, that they are aware of everything that is going on at this point, and are most likely even “fascinated” by all the attention he is receiving.

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Cardinale praised the NYPD and FBI, saying they did everything right in this investigation and took every tip seriously.

“I’m sure there are clues because someone, this man’s face, is on a national platform right now in all the media and someone has to recognize that person and he (the person of interest) has to know that. “He needs to know that he left these clues, and I think if he gets caught, he’ll make it his real moment,” Cardinale said.

The manhunt has now spread to several states and reached its fifth day on Sunday.

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The FBI released new images of the wanted person on Sunday and is now offering a reward of up to $50,000 for information leading to the arrest of the suspect.

Anyone with information is asked to contact Crime Stoppers at 1-800-577-TIPS or in Spanish, 1-888-57-PISTA. Tips can also be submitted on the Crime Stoppers website at crimestoppers.nypdonline.com.

Fox News Digital’s Christina Coulter, Christina Shaw and Ashley Papa contributed to this report.

Stepheny Price is a writer for Fox News Digital and Fox Business. Story tips and ideas can be sent to [email protected]