In the case of a missing husband and father in San Francisco, police said Thursday they found a vehicle at San Francisco International Airport connected with the person of interest.

Piseth Chhay, a 48-year-old Uber driver and father of two, has been missing since Mother's Day, and police identified an acquaintance of the family, Bob Tang, as a person of interest. On Tuesday, Tang also went missing, and police believe he may have fled to Cambodia.

The vehicle associated with Tang is a 2004 Silver Toyota Sienna SUV, with California license plate 5JOT221, police said Wednesday. It was not clear if that's the vehicle found at SFO.

Meanwhile, Chhay's wife, Rattana Kim, said Tang is a family friend her kids call "Uncle Bob," and she was shocked to hear he might have harmed her husband.

"Why is it someone who we consider a brother or a uncle? Why would he do that, especially when you have your own family, two sons of your own?" Kim said.

Kim said she doesn't know what happened between Tang and Chhay on May 14. But she does know two families are suffering.

"I have not talked to (Tang's) wife," she said. "She's probably going through hell like I am."

The SFPD Special Victims Unit continued to investigate the case Thursday, serving search warrants in the cities of Hayward and San Francisco.

Tang, 48, had agreed to come in for an interview with police Tuesday but didn’t show, police said. He is described as an Asian male, about 5 feet, 4 inches tall, weighing 130 pounds, with brown eyes and black hair.

Jean Elle/NBC Bay Area

Chhay's vehicle, a Mercedes Benz SUV, was found stripped Friday in the city's Bayview neighborhood, and police believe it may have been moved there.

Searches were conducted at three locations Tuesday, two in San Francisco and one in Antioch, police said.

Though he was not working on the day he disappeared, Chhay told a relative that an Uber customer had left a phone in his vehicle, and he wanted to return it.

Anyone who has seen either Tang or Chhay or has any information regarding their whereabouts should contact San Francisco Police via the anonymous tip line at 415-575-4444, or text a tip to TIP411 with SFPD at the beginning of the message.

A GoFundMe account has been set up and can be viewed here.