Carroll County sheriff’s deputies will try to use cell phone signals to triangulate the location of a father and son who have been missing since last Wednesday.

David Decker, 32, borrowed a friend's car and headed for Carroll County to pick up his dad, 52-year-old Ernest "Bob" Decker.

Now a week's gone by and there's no sign of either man.

"No one has heard from these two,” said Carroll County Sheriff Dale Williams. “Both carry cell phones, both phones automatically go to voicemail when you call the phones."

Over the weekend, friends found Bob Decker's pickup truck on his land in Brown Township. The keys were in the ignition and a pair of glasses spattered with blood were found in the truck-bed.

Investigators aren't sure if the glasses are Bob Decker's, so DNA testing is under way.

"We cannot find any evidence of foul play other than the glasses,” said Williams. “So we're just trying to find additional leads and we're following up on everything we do have."

The borrowed car is a red 1997 Mercury Tracer with Ohio license plate DD18QL.

Investigators dredged a pond on Bob Decker's property in Carroll County on Monday and found nothing of interest.

Eric Minor, NEWS9