U.S. President Barack Obama on Thursday met with senior administration officials on the search and rescue effort to rescue 11 missing workers after an oil rig explosion, vowing to offer all assistance needed of the federal government.

Obama was briefed in the afternoon by a number of senior officials on the situation around the Deepwater Horizon rig, which sank into the ocean earlier in the day after burning for about 40 hours.

The Coast Guard informed Obama that search and rescue efforts are ongoing. Obama ordered the entire federal government to offer all assistance needed in the rescue effort as well as in mitigating and responding to the environmental impact.

He also asked responding departments to investigate the cause of the incident.

An explosion at the platform Tuesday night caused the fire, and 11 workers were missing after the explosion. Authorities have been looking for them non-stop. The rig is owned by Transocean, and under contract to oil giant BP. It is located at about 82 km southeast of Venice, Louisiana.

Officials present at the meeting included Homeland Security Secretary Janet Napolitano, Coast Guard Commandant Thad Allen, Interior Secretary Ken Salazar, Environmental Protection Agency Deputy Administrator Bob Perciasepe, and Federal Emergency Management Agency Administrator Craig Fugate.

Senior White House officials also participated in the meeting, including Chief of Staff Rahm Emanuel, Assistant to the President for Energy and Climate Change Carol Browner, Chair of Council on Environmental Quality Nancy Sutley and Director of the National Economic Council Lawrence Summers.

According to the White House, the National Response Team has been activated and Unified and Area Commands have been established near New Orleans to coordinate search and rescue operations and oil spill response efforts.