WASHINGTON -- Police have arrested a Maryland construction worker for shooting a co-worker with a nail gun following an argument at the site where the two were working.

Guillermo L. Lopez-Molina of Hyattsville, Md., has been charged with first and second-degree assault and reckless endangerment.

The 34-year-old victim was found just before 11:30 a.m. on Monday, "suffering from injuries to the upper body sustained from a nail shot from a nail gun while framing a house," according to a media release put out by the Anne Arundel County Police Department.

Police originally thought the shooting in Mayo, near Annapolis, was accidental, according to the release. But "further investigation consisting of several interviews revealed that the victim was involved in a dispute with another member of the crew working on the home. At a certain juncture, the co-worker shot the victim with a nail gun."

The victim, whose identity has not been revealed, was taken by helicopter to a Baltimore hospital with what may be life-threatening injuries.

Capitalgazette.com reports that Lopez-Molina is being held on $250,000 bond, awaiting a bail hearing.