The boom on a crane, owned by Marr Scaffolding Co., snapped recently, killed a 45-year-old ironworker, the Boston Globe reported. The crane was unloading steel beams from a tractor trailer bed, according to witnesses and officials.

Witnesses said ironworker Adam Boudreau was standing near the crane at the rear of the truck bed as the crane lifted three or four beams, which, witnesses said, did not strain the crane.

Jeffrey Marr, of the South Boston-based Marr Cos., could not immediately explain why the boom failed.