A work truck from a Texas plumber is being used by an Islamic militant group with the logo still intact, resulting in angry and even threatening phone calls for the truck's former owner.

"To think something we would use to pull trailers, now is being used for terror, it's crazy. Never in my lifetime would think something like that," Jeff Oberholtzer, the son of Texas City-based Mark-1's owner, told KHOU News.

A small-town business, Mark-1 is now fending off phone calls from across the county after the militant group posted a photo of the vehicle on its Twitter feed. The former Mark-1 truck has been repurposed as an anti-aircraft weapon used on the front lines of the civil war in Syria.

"We have a secretary here, she's scared to death. We all have families. We don't want problems," said Oberholtzer.

How did the truck end up in such different hands?

After Oberholtzer traded the truck in last year at the AutoNation Ford dealership on the Gulf Freeway in Houston, it immediately went to auction. The vehicle likely went through a number of owners before apparently falling into militant hands.

The Chechen group named Jaish al-Muhajireen wal-Ansar comprises Chechen and Russian fighters as well as some recruits from Europe and the United States.

Oberholtzer and Mark-1's takeaway lesson from the bizarre turn of events was that all company stickers and logos should be removed from vehicles before they go to different owners.

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