Four employees of a Massey Energy-owned coal mine have pleaded guilty to US federal misdemeanour charges in relation to the deaths of two men in a conveyer belt fire.

The employees admitted that they failed to lead the crew on a required escape drill from Massey’s Aracoma Alma No 1 mine at various times in 2005 and 2006.

On 19 January 2006 two miners died after getting lost as they tried to escape from the sprawling underground Logan County mine, West Virginia.

Last year Aracoma Coal, which operates the mine, paid $4.2m in criminal fines and civil penalties related to the fire, according to Bloomberg.

Massey’s Upper Big Branch mine is being probed with criminal and civil charges for an explosion that killed 29 men in April.