The boyfriend of a woman who vanished in West Texas earlier this month is now officially a suspect in her disappearance, police announced as they shifted the search area closer to the Mexico border.

Zuzu Verk, a 22-year-old Sul Ross State University student, was last seen Oct. 12 in Alpine on a date with Robert Fabian.

Alpine police said Wednesday that Fabian was a suspect in the case and his sister, mother and friend were persons of interest, Fox 4 reported. Police raised the reward to $100,000 for information leading to the student's whereabouts.

MISSING COLLEGE STUDENT'S FATHER PLEADS FOR HER BOYFRIEND TO COOPERATE

Investigators and Verk’s family have said Fabian hasn’t been cooperating with authorities -- a claim his lawyer denies.

"I drove all night as soon as I heard Zuzu was missing, and when I got there, a search was already in progress," Verk’s father, Glenn, told FoxNews.com earlier this week. "Everyone wanted to help, but he [Verk's boyfriend] wasn't there."

2 FORT CAMPBELL SOLDIERS BEING HELD IN DISAPPEARANCE OF FELLOW SOLDIER

Fabian is named in more than one police search warrant surrounding vehicles that investigators believe to be important in the search for Verk, Fox 4 reports. The vehicles include a Jeep and a Mazda Miata, which friends say is Zuzu’s car, while a white Ford Mustang and F-150 truck that are linked to Fabian’s family.

Police, using drones and horses, have now moved their search near the U.S.-Mexico border and are being assisted by the Texas Rangers, FBI and Homeland Security. Alpine is 210 miles southeast of El Paso.

Sul Ross State has about 2,100 students. President Bill Kibler on Thursday released a statement saying Verk's disappearance has deeply affected the entire campus community, plus the surrounding area.

School spokesman Steve Lang on Friday said students, faculty and staff have taken part in voluntary searches coordinated through Alpine police.

Investigators have said Verk could be in danger. Police didn't release additional details.

A $100,000 reward is being offered for information leading to Verk’s safe return and tipsters are encouraged to call the Alpine Police Department at 432-837-3486.

FoxNews.com's Cristina Corbin and The Associated Press contributed to this report.