The Texas teen who mysteriously vanished from her home early Christmas Eve is feared to be in “imminent danger,” as investigators say the case may lead them outside the United States.

Camila “Cami” Mendoza Olmos, 19, was last seen outside her San Antonio home just before 7 a.m. Wednesday, wearing pajama shorts and a hoodie.

Bexar County Sheriff Javier Salazar said deputies and volunteers have been searching around the clock for the teen, adding that investigators are “not ruling out that this case may take us outside the borders of the continental United States,” CBS News reported.

“We definitely don’t want to miss anything,” Salazar said.

Authorities are exploring all possibilities in Olmos’ disappearance, including kidnapping, human trafficking or the chance she left on her own, Salazar said.

The sheriff noted the teen had recently gone through a breakup but said it was mutual, adding that investigators do not suspect anything “nefarious” and that those close to her are cooperating.

Salazar also confirmed that Olmos was not detained by US Immigration and Customs Enforcement, noting that she is a US citizen.

“That was a personal concern,” he said. “So I had it checked to make sure there were no stops, no detentions, and that she’s not somewhere in a federal detention facility. That is something we needed to check.”

Olmos was captured on video outside her home rummaging through her car before the footage cut off, according to the Bexar County Sheriff’s Office.

Authorities said she never returned home and left her car behind, leading investigators to believe she departed on foot with only her car keys and possibly her driver’s license.

Olmos’ mother, Rosario, woke up Wednesday unable to find her daughter, who typically took an early-morning walk.

By 9:30 a.m., she grew concerned and tried calling her daughter, only to find Olmos’ phone on a bed with a dead battery.

Salazar said it was “highly unusual” for Olmos — who leads an active lifestyle — to leave her phone behind and not return.

“That’s why we’re working basically around the clock on this case,” he told CBS News.

While Salazar declined to share specific details, he said investigators fear the teen may be in “imminent danger.”

Federal authorities, including the FBI and the Department of Homeland Security, are assisting in the search by monitoring border crossings and international travel.

Olmos’ childhood best friend, Camila Estrella, said the two spoke on the phone Tuesday about going dress shopping for an outfit for Estrella’s boyfriend’s family event.

“She said, ‘Bye Cami, I love you,’” Estrella recalled. “She was someone who was just full of love.”

“This is so random — we never expected this.”

Anyone with information on her whereabouts is urged to contact the Bexar County Sheriff’s Office at (210) 335-6000 or email the BCSO Missing Persons Unit at [email protected].