ALPINE, Texas -- The boyfriend of missing 21-year-old Zuzu Verk has officially been deemed a suspect in her disappearance by local authorities, and new documents obtained by News 8 may provide an explanation as to why.

In search warrants obtained exclusively by WFAA, authorities state that the boyfriend, Robert Fabian, called his friend Chris Estrada twice during the early morning hours of Verk’s disappearance on October 12. The warrant affidavit also indicates they communicated using the social media app Snapchat around that same time.

A separate warrant pertaining to a pick-up truck indicates that Fabian borrowed the F-150 during those same early morning hours on that Wednesday.

None of the revelations come as a surprise to John Franco, who lives directly below Fabian in an apartment complex across from Sul Ross State University.

"That night, we heard arguing," said Franco. "I can hear him pacing back and forth, in the kitchen, living room, all around, all around.”

Franco said his girlfriend woke him up a short time later.

“Going down the stairs, we heard a loud thump. This is around 4 in the morning," said Franco. "I only wish we had done something."

Another search warrant for Estrada’s Ford Mustang says that in the days following Zuzu’s disappearance, Fabian was acting “very nervous,” and that Estrada attempted to get his car cleaned three times at a local auto shop.

1024 Robert Fabian and Zuzu Verk
Robert Fabian and Zuzu Verk.

“Something was definitely different that week," says Josh Cobos, whose family runs the shop.

Cobos says he was a close friend of Fabian's, and that he was acting strangely when he stopped by the shop two days after Zuzu disappeared.

“Something in my gut says I think he knows something," Cobos said

In an interview, Cobos also revealed that Fabian left his laptop at Cobos' home in the days after Zuzu went missing. Cobos says he turned it over to the police.

A warrant obtained for the laptop doesn't reveal what, if anything, was recovered on the device but it does state that the computer "...contained items that Robert Fabian wanted to remove from social media."

Estrada remains a person of interest in the case, although authorities say he has been cooperative. Fabian's family are also now persons of interest, according to Chief Russell Scown.

"We are going to bring in the Attorney General's office to hopefully convene a grand jury," said Scown.

If subpoenas are issued, Scown said that could force certain people to testify about what they know of Zuzu's disappearance.

Authorities on Wednesday also continued drone and aerial searches, focusing around town and south in Presido County. Sheriff Ronny Dodson said nothing came of the search there.

News 8 spoke to Verk family on Tuesday. They expressed confusion and frustration that Fabian would not cooperate with investigators, and promised to stay in Alpine "as long as it takes" to get news of their daughter.

The family met with his attorney, Liz Rogers, over the weekend, but learned “nothing,” according to Verk’s father.

“It was not productive,” he said.

Rogers has continually denied requests for comment on the case.

A prayer vigil was held Wednesday evening at Sul Ross State University, where Verk was a biology student. Close to 150 friends and strangers gathered to hold out hope for a safe return.

A $100,000 reward for information regarding Verk's disappearance remains active.