KNOXVILLE, Tenn. — The Knox County Sheriff's Office says dozens of guns have been stolen so far in 2019 from unlocked cars in the county. 

"We're talking about handguns that are now out into the," Lt. Allen Merritt paused. "Who knows where they're at."

The sheriff's office says guns stolen here in Knox County are sometimes used to commit violent crimes in other areas. 

"That stolen gun that was stolen from an unlocked vehicle ended up in another state and a person used it to kill someone else," Merritt, who heads the property crime division, said. 

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Of the 42 guns stolen from unlocked cars, owners didn't know the serial numbers for ten of them, making it nearly impossible for investigators to find the guns. 

"Without a serial number, we can't enter it to the database. Therefore the chances of that gun ever being recovered are very slim," Merritt said.

To try to find the guns, the sheriff's offices uses crime tracking software and maps out reports of thefts and where criminals are known to operate.

"If we can develop a pattern of burglaries that have occurred, than we can look at patterns of offenders that have occurred in that area as well," Capt. Aaron Yarnell of the technology division said. 

Police in Memphis and Nashville are also reporting more stolen guns. Knox County investigators say Tennessee's law which allows people to keep guns in their cars without a permit has made the problem worse. 

"Unfortunately what we see is people kind of get complacent. 'Okay, I can carry my gun in my car, I'll put it in my car and leave it in my car,'" Merritt said. "'We don't think we're going to be victims.' 'Oh, that will never happen to me.' But it will and it can." 

Investigators warn that thefts are more common when the weather gets nice. 

They say the solution is simple. If you own a gun, lock it up inside overnight or put it in your trunk. Investigators say putting it under the seat or in the glove box just isn't enough.