Ibrahim Nofal vanished nearly a week ago from the shop. Investigators say he may have been abducted.
Nofal's family believes that he has been abducted, and has increased the reward to $50,000 for information leading to his whereabouts.
"We feel Ibrahim's alive," said Nofal's cousin, Mohammed. "We feel he's out there, and we're confident he's going to come back to his family."
Nofal's family has not heard from him in six days. The 28-year-old father of two was reported missing from his auto repair shop after a brother arrived there late Tuesday night and found the shop's garage door and Nofal missing.
Nofal's family has been organizing daily prayer vigils at the auto repair shop. On Sunday, they organized a search of the wooded area surrounding the business.
"We are not eating. We are not sleeping, including myself," said Mohammed Nofal. "This has been very, very tough. We want him home. We want him back."
Police released surveillance video of a 1996-2001 Jeep Grand Cherokee entering and exiting the shop's garage Tuesday afternoon and are looking for people who could be able to identify the car.
Police say they saw two men get out of the Grand Cherokee and approach Nofal.
Investigators believe it was likely that Nofal was inside the jeep when it left the area.
"Investigators believe that it is likely that Ibrahim was inside the Jeep when it left the area," said Orland Park Police Chief Tim McCartney. "It is unknown if Ibrahim left the business voluntarily or against his will."
Meanwhile, Joliet police are working to identify a body found in Joliet's Pilcher Park Saturday afternoon, although police have been unable to identify the body due to the heat in the area last week. Police said the body is not connected to any open missing persons cases in Joliet.
Word on the Joliet body is expected by Tuesday night.
"The lack of a motive, I think, would be the biggest challenge, is that, you know, if we had some evidence that it was a robbery, if we had some evidence that it was a -- there is just no clear motive here," said McCartney.
The auto shop remained closed Monday while family stayed at the police station. Friends said that someone is staying at the shop nearly around the clock just in case.
A 24-hour hotline has been set up for the case, (773) 299-0277. The email address is firstname.lastname@example.org.