Gavin Smith investigation 'moving forward vigorously,' official says Detectives have analyzed a "significant amount of evidence" in their investigation into Fox executive Gavin Smith's disappearance, and the case is "moving forward vigorously," a sheriff's official said. But investigators don't necessarily feel pressed for time, as their person of interest remains behind bars on an unrelated drug conviction. John Creech - whose wife, authorities said, had a "relationship" with Smith after meeting him in rehab - is serving an eight-year sentence at Men's Central Jail. Even if Creech were to be released early for "good-time, work-time" credit, sheriff's spokesman Steve Whitmore said Friday, he would still spend four years in jail - a place "where he can be interviewed at any time." "He's a captive audience," Whitmore said. Creech has not spoken to investigators while in jail, sheriff's Lt. Dave Dolson said, but his wife has talked to detectives on multiple occasions. Dolson declined to elaborate on what Chandrika Creech said or the nature of her relationship with Smith. Although investigators have already looked at a "significant amount of evidence," Whitmore said, additional evidence still needs to be examined. More than two dozen search warrants have been served in connection with the case, he added. "So there is still evidence that needs processed and analyzed," he said. They are not putting a time frame on that, but it's moving forward vigorously. But Thursday, they announced they believed Smith had been killed, though no body has been found. Officials also revealed that Smith's Mercedes Benz, missing since his disappearance, was found last month in a Simi Valley storage locked linked to Creech. "The condition of the vehicle in conjunction with cooperating witness statements indicates he was killed," Dolson said. Subsequent searches of Creech's home and business yielded drugs, cash and other items. Creech later admitted to police that he was a middle-man between drug producers and lower-level street dealers, and pleaded no contest last year to one count of selling and transporting cocaine. In January, authorities searched his Hummer after it was found at a marijuana grow house in Granada Hills. Creech's West Hills home was also searched at least twice last summer. Smith's wife, Lisa, told The Times on Thursday that she and her three sons were "devastated" by news that detectives believe her husband was killed, but is hopeful that authorities will find out "exactly what happened" and "bring it to justice." Matthew Keys 'fine' after indictment on hacking charges 12-year-old who gave pot brownie to kids at school arrested Dorner case: Women shot at by LAPD could get $40,000 payment soon Andrew Blankstein, Richard Winton, Kate Mather and Daniel Miller