Golden Star said the fatalities occurred on December 29 and the operations were suspended to allow for a full investigation.

Prestea Underground resumed full operations on Monday and mine management and Ghana's Inspector of Mines were conducting further investigations.

The company said initial results suggested the pair had succumbed to smoke inhalation sickness following exposure to blasting gases.

Golden Star CEO Sam Coetzer extended condolences to the pair's families and friends.

"Safety is our highest priority and we take great care in ensuring that all of our underground team members have self-rescuers and that they are trained to use them correctly," he said.

"We are conducting further investigations to understand why this tragedy occurred and how to prevent it from happening again."

The fatalities were a sad finish to a triumphant 2017 for Golden Star, whose Prestea operations were named Ghana's mining company of the year in November.

Prestea had 715 employees and 1,197 contractors in 2016. Golden Star operates the Prestea and Wassa gold mines in the West African country.