While unpacking a case of frozen meat, a New Mexico grocery store employee found a loaded gun packed with seven rounds of ammo. KOB's Erica Zucco reports.

A supermarket employee in Roswell, N.M., found an unexpected item in a case of frozen meat this week: a loaded handgun.

The Albertsons worker was unwrapping the meat, which had been shipped from a packing plant in Colorado, when he discovered the firearm, along with seven rounds of ammunition, on Wednesday.

"The big cases of meat come in a box," Sabrina Morales, Roswell Police Department public relations liaison, said. "When he opened it, he saw the firearm. It wasn't packaged inside with the meat, but it was in the same box."

The man brought the Rock Island Armory .38 super semi auto handgun, along with the ammo, into the Roswell Police Department at about 2 p.m. that afternoon, she said.

Where the gun came from is a mystery to police. It was entered into the National Crime Information Center database, but no reports of its being stolen came up.

The supermarket employee wiped it clean before turning it in, making it difficult for police to find any identifying fingerprints.

Adding to officers' challenge: The meat, which was sent to Albertsons from Swift Packing Plant in Greeley, Colo., was packaged more than a year ago.

"The other part that's disturbing is the date on the package was 6.8.2011. I don't know how long meat stays well-frozen, but that was the date of the package he was opening," Morales said.

A call to Swift Packing Plant's corporate office from NBC News was not returned Friday. Roswell police, who did not identify the Albertsons employee, said they have collected all the information they can and have turned the investigation over to Greeley police.

In the meantime, Roswell police are hoping their NCIC database query through the federal Bureau of Alcohol, Tobacco and Firearms may provide some clues, but Roswell Sgt. Jim Preston told New Mexico's KOB.com that the search could take months.

"If it was stolen, we would have thought that by now it would have been entered into the actual database, NCIC, as a stolen firearm," he said. "But we don't have any of that information, and it is something we're looking into."

The gun has made for one of the more memorable cases for the Roswell department.

"You hear of people finding frogs in their salad or weird stuff like that, but never heard of this one," Morales said.

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