Luigi Mangione Yells to Cameras as He's Rushed Into Courthouse by Cops

The suspected killer of the UnitedHealthcare CEO began shouting toward media cameras as he was quickly rushed into a Pennsylvania courthouse on Tuesday ... where he will face his extradition hearing.

Luigi Mangione began shouting as soon as he was led out of a police van in an orange jumpsuit ... saying in part "... Completely out of touch and an insult to the intelligence of the American people!"

It was difficult to make out exactly what the suspect was saying ... 'cause as soon as he started his stunt, officers roughly manhandled him inside.

Mangione is facing a slew of charges for the murder of CEO Brian Thompson ... after allegedly shooting Thompson in NYC last week. He's likely to be extradited to New York Tuesday to face charges there.

Monday morning ... Mangione was busted in Altoona, Pennsylvania as he sat inside a McDonald's restaurant. A customer recognized Mangione from widely circulated wanted posters following Thompson's murder, and told an employee ... who then contacted local police, who responded and cuffed the suspect.

Authorities recovered the alleged pistol Mangione used in the murder and a 3-page manifesto he'd written railing against corporate America and the healthcare industry, according to police.