NEW VIDEO: Hours of newly unsealed bodycam footage show Luigi Mangione's arrest and the moment officers searching his backpack realize who they have in custody. "It's f ing him. 100%." The video takes viewers inside the McDonald's where Mangione was arrested after a five-day manhunt following the killing of UnitedHealthcare CEO Brian Thompson. Officers are seen questioning him after he presents a fake ID, then discovering a gun magazine during their search. Mangione later pleaded guilty to two federal stalking charges and admitted to shooting Thompson. Now his attorneys argue that plea should stop New York's murder prosecution from moving forward. @​BryanLlenas Download the FOX News app to follow this developing story: ▻