JUANA SUMMERS, HOST:

We are watching the latest developments regarding yesterday's apparent assassination attempt of former President Donald Trump. The suspect made his initial appearance in federal court today. Federal agents are digging to learn as much as possible about him. And officials provided an update today on that investigation. NPR justice correspondent Ryan Lucas was listening. Hey there.

RYAN LUCAS, BYLINE: Hi there.

SUMMERS: So, Ryan, what can you tell us? What's the latest from that briefing today?

LUCAS: Well, the suspect, Ryan Wesley Routh, was taken into custody just over 24 hours ago. So it is still very much early in this investigation. But FBI special agent Jeff Veltri told reporters that the FBI is digging into Routh's life. They're aggressively trying to figure out everything that they can about him. They've executed search warrants for his cellular phones, his car, electronic devices, in places where he's lived. They've interviewed seven civilian witnesses who were on the scene. Agents in Hawaii, in North Carolina, where Routh had lived, are interviewing friends, old colleagues, family.

Agents are also combing through Routh's pretty extensive social media history. He was very active online. And agents will also try to piece together, to reconstruct his movements in the hours, days and weeks leading up to what happened yesterday at the golf course. As you said, Routh was in federal court today. Now he faces two gun charges as of now, but he could face additional charges, of course, in the days to come.

SUMMERS: Ryan, let's talk about that weapon, the gun that they recovered. Do authorities have a sense of how he got it?

LUCAS: Well, this was an SKS-style rifle, a semi-automatic. Agents recovered it at the scene, along with a digital camera, a plastic - food with bag as well and a couple of other things. The FBI said that the gun's serial number, though, was destroyed. And that, of course, is going to make tracing the gun and figuring out where Routh got it more difficult. It's going to take more time.

But there are two other things in this investigation that have caught my eye. Court papers say that the Nissan SUV that Routh was driving when he was pulled over had stolen license plates on it. And another thing is that court papers say the cellphone usage data indicates that Routh was in the bushes or the tree line along Trump's golf course for 12 hours - from 2:00 a.m. until the time he was finally seen by Secret Service in the early afternoon.

All of that points to a degree of planning, of premeditation. That raises a lot of questions, including, of course, whether he was acting alone. The FBI says they are taking a look at that question, but they don't have any information at this point that Routh had any accomplices.

SUMMERS: And what about the Secret Service? What has the Secret Service had to say about its role in all of this?

LUCAS: Well, the Secret Service, of course, came under a lot of criticism after that attempted assassination in Pennsylvania two months ago. Acting Secret Service Director Ronald Rowe is in Florida now. He addressed reporters at this news conference. Here's a bit of what he had to say.

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RONALD ROWE: Yesterday afternoon, this country was reminded of the heightened and dynamic threat environment the United States Secret Service and its protectees face on a daily basis.

LUCAS: Now, Rowe defended the Secret Service's actions yesterday. He said Trump's protective detail has been beefed up significantly since the assassination attempt a couple of months ago. He said it is at the highest level now.

In the case yesterday, a Secret Service agent on Trump's protective detail was walking the perimeter of the course. The agent saw what looked like a rifle poking out of the bushes, opened fire. A witness then saw a man, later identified as Routh, flee the bushes, jump out of there - the tree line - jump into a Nissan SUV and speed away. Local officers located the car on the highway and pulled him over.

Now, Rowe said Trump was not originally supposed to go to the golf course. It was an unplanned thing. But he said the gunman never had a line of sight on Trump, never got a shot off. So he said the Secret Service's processes here worked, and it worked as designed.

SUMMERS: Quick answer here, Ryan - is there anything specific you're keeping an eye on as this investigation moves forward?

LUCAS: Motive and, of course, whether there were any accomplices or whether he acted alone.

SUMMERS: NPR justice correspondent Ryan Lucas. Thank you.

LUCAS: Thank you. Transcript provided by NPR, Copyright NPR.

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