Workers on a platform about 17 miles off the coast of Louisiana sparked a blaze while cutting into a pipeline that contained oil. One worker was killed and several others suffered severe burns.
The rig, operated by Black Elk Energy, wasn't in service at the time of the incident and no visible sheen was associated with last week's accident.
The company announced late Tuesday that it abandoned search-and-rescue efforts for one remaining crewman.
"Based on the advice and counsel of search rescue experts who have been engaged in this effort since the outset, Black Elk Energy Offshore Operations, LLC announced Tuesday evening it will suspend formal search and rescue efforts after more than 100 hours," a statement read.
Investigators with the U.S. Bureau of Safety and Environmental Enforcement have met with rig workers and other parties to get first-hand accounts of the accident. The company this week was subpoenaed by the U.S. Chemical Safety Board for its investigation.