A body-worn camera video shows police officers approaching Luigi Mangione before they arrested and searched Luigi Mangione at a Pennsylvania McDonald's — moments that underlie key questions about what evidence can and can't be used in the case surrounding the killing of UnitedHealthcare CEO Brian Thompson.

The footage was taken on Dec. 9, 2024, five days after Thompson was gunned down on a New York City sidewalk. Officers' body cameras captured the roughly 20 minutes between police approaching Mangione at the restaurant and telling him he had the right to remain silent.

Moments after Luigi Mangione was handcuffed at a Pennsylvania McDonald’s, a police officer searching his backpack found a loaded gun magazine wrapped in a pair of underwear.

The discovery, recounted in court Monday as Mangione fights to keep evidence out of his New York murder case, convinced police in Altoona, Pennsylvania, that he was the man wanted in the killing of UnitedHealthcare CEO Brian Thompson in Manhattan five days earlier.

Thompson, 50, was killed as he walked to a Manhattan hotel for his company’s investor conference on Dec. 4, 2024.

Mangione was arrested in Altoona, about 230 miles (370 kilometers) west of Manhattan, after police there received a 911 call about a McDonald’s customer resembling the suspect.

Mangione, 27, has pleaded not guilty to state and federal murder charges.