The number of people killed by a gas explosion in an unused coal mine in South Africa’s eastern province of Mpumalanga has risen to six, and several others remain trapped, an official at the mine said on Thursday. The representative of the creditor protection team at the mine, Michael Elliot, said more than 20 people were still stuck underground at the mine in Middelburg and are presumed dead. "As I’ve been informed, there are six deceased people in this point in time that have been taken to the mortuary," Elliot told Reuters over the phone.