PALATKA, Fla. -- A 15-year-old Putnam County girl who was the subject of a nationwide search and her 22-year-old boyfriend were picked up by police in El Paso, Texas, Saturday afternoon.

A motorist recognized Morgan Amanda Leppert and Toby Lee Lowry after seeing a television report of the Amber Alert and called police just after 4 p.m.

Officers said Leppert, Lowry and a third person they believe was a hitchhiker were panhandling just off Interstate 10.

The stolen 2003 Toyota Tacoma pickup they were driving was found nearby. The pickup belonged to 66-year-old James Stewart, who was found violently killed in his Melrose home on Thursday.

Putnam County Sheriff Dean Kelly said Leppert is in good shape physically and emotionally.

"I've spoken with her mother, who is obviously elated that she is safe," Kelly said.

Putnam County investigators had searched for the San Mateo teenager since her mother reported her missing on April 22, but the case was elevated to an Amber Alert when deputies made the connection between her disappearance and the homicide.

Lowry has a lengthy criminal history, with arrests in both Putnam and Clay counties. He was released last summer after serving a 20-month sentence for burglary and criminal mischief.

Deputies received three reports of the stolen vehicle headed west on I-10, the most recent was early Thursday morning near Houston.

The man who spotted the couple Saturday afternoon said he turned around to get a better look at them before he called authorities.

"I was pretty sure I recognized them from the TV show this morning," Stacy Fuller told Channel 4. "I pulled over up a little and got the sheriff's number and explained to him what I'd seen and that I though it was the couple I'd seen on TV."

Putnam County Capt. Keith Riddick said Lowry was being held on existing warrants charging him with grand theft of the vehicle and interference with custody of a child. Lowry is also considered a person of interest in the Stewart homicide case. He's also being charged with panhandling in Texas.

Riddick said Leppert was not charged with panhandling.

An investigator with the 7th Judicial Circuit Homicide Investigative Unit was already in Texas on Saturday working on the case. He is joined by a Putnam County detective and they hope to interview Leppert and Lowry as soon as possible.

"The interviews that are about to take place in the next 24 to 48 hours are absolutely critical and, hopefully, will answer all the questions we all have," Kelly said Saturday night.