President Obama is requiring an initial report from federal mine safety officials next week on the explosion at a West Virginia coal mine Monday that killed at least 25 workers, the White House announced Thursday.

The explosion at Massey Energy Co.’s Upper Big Branch mine – a mine that federal regulators have cited for numerous safety violations – is the nation’s worst mining accident in over two decades.

Obama has tasked the officials with producing an initial assessment on the causes of the accident and “what actions could prevent further tragedies in this industry,” the White House said.

Obama will meet with Secretary of Labor Hilda Solis and Mine Safety and Health Administrator Joe Main. 

“He expects them to report on their early assessment of the deadly explosion’s cause, the safety record at the Upper Branch mine, and the steps that the Federal government should take to improve safety enforcement and prevent future tragedies,” the White House said. “The Secretary and MSHA Administrator will address safety issues as well as enforcement and legal authorities in their briefing.”

Senior Capitol Hill lawmakers such as House Education and Labor Committee Chairman George Miller (D-Calif.) have also pledged to investigate the accident and possible changes to federal mine safety laws.

Rescue teams are trying to gain access to the mine to seek four workers that remain missing, but dangerous gases have thwarted the operation thus far.

The rescue officials hope the workers were able to reach underground chambers that have food and water.