Despite living in a technology-driven age, NYPD officials say it was methodical police work done by human beings that ultimately led to the arrest of Luigi Mangione, the 26-year-old man accused of killing UnitedHealthcare CEO Brian Thompson in Manhattan last week.

“I think everybody assumes that this is all automatic in this age of AI and cutting-edge tech — and there is a lot of tech out there — but, really, this is hard work by human beings who are doing those canvasses,” said Rebecca Weiner, the NYPD’s deputy commissioner for intelligence and counterterrorism, referring to how detectives gathered video evidence of the suspect’s movements throughout the city. Weiner was interviewed on "Mornings On 1" Wednesday.

Now sitting in a Pennsylvania jail as he fights extradition to New York, Mangione left behind a trail of clues—a coffee shop visit, a hostel stay, a ride on a bicycle, and later, a taxi—reconstructed by investigators combing through hours of video footage.

While the city’s Lower Manhattan Security Initiative, which consists of 70,000 networked cameras cloaking the area, proved pivotal to tracking Mangione’ movements, it was the officers who got the job done, she said.

“Ultimately, you have to put together, with human beings and their acumen, all of these movements — aided, of course, by this technology, but the technology piece never can stand alone,” Weiner said.

Mangione was arrested Monday in the Dec. 4 attack on Thompson after police say a worker at a McDonald’s in Altoona, Pennsylvania, alerted them to a customer who resembled the suspected gunman. 

During his arrest, Mangione was found with a gun that investigators believe was used in the attack and writings expressing anger at corporate America, police said.