According to an Associated Press report, two events have slowed the rescue/recovery process at Tri-Star in western Maryland: a mechanical shovel that became wedged in mud for nearly seven hours, and stoppage in rescue work while workers set off explosives to bring down rock and debris that were posing safety hazards to rescuers.

While the US Mine Safety and Health office in Washington has not yet released an official statement regarding the incident or the two victims, a MSHA official at the site confirmed that they had not yet been found.

Also, engineers said it appeared the highwall collapsed from the bottom, pushing the men and their vehicles to the outer edge of the pile that now stood at the mine.

The accident occurred around 10am local time Tuesday.

It is estimated the two miners were initially buried with their equipment under approximately 75 feet of rock and debris.

MSHA has maintained that their names will not be released until an outcome has been reached.

Various media outlets reported earlier this week that the collapsed section measured 300ft long by 60ft high.

Keep watching International Longwall News for further updates on this incident.