Live in Times Square, this is Good Morning America.

We're going to begin, of course, with a suspect that is charged in the murder of United Healthcare CEO, Brian Thompson.

Fighting extradition back here to New York.

Luigi Mangione appeared in a Pennsylvania courtroom yesterday.

You can see him shouting angrily as he entered the

building. Law enforcement now focusing on alleged writings by Mangione for clues about a potential

motive. We're going to speak to his lawyer in a moment, but first let's go to senior investigative

correspondent, Eric Kuturski, outside the prison there in Pennsylvania with the latest force.

Good morning to you, Aaron.

Good morning, Robin.

The 26-year-old suspect is now being held at this prison without bail after fighting extradition and shouting those fighting words that officials now fear could be considered a call to action.

An outburst from Luigi Mangione, shackled and handcuffed as he was dragged into court.

And it's completely out of touch.

And as an insult, he tells us as the American people.

It's life experience.

Sheriff's deputies wrestling him inside.

He refused to waive extradition to New York, where he's charged with murdering United

Healthcare CEO Brian Thompson.

When I entered my appearance, and for the record, he's pleading not guilty to those.

And I've seen zero evidence at this point.

The judge denied bail. Menjioni kept quiet as he left court, head down.

He's a threat to no one.

...