The largest mobile crane in the United States collapsed at a Houston oil refinery on Friday, killing four workers and injuring six others. The crane fell over at a Lyondell-Baseli refinery in southeast Houston, falling on or knocking over a smaller nearby crane. The casualties were in the area of the crane, but officials still are not certain whether they were on the crane or under it, said company vice president for refining John Roecker. “This is a traumatic experience for all of us. We have to focus on the safety and health of our employees,” he said.
