Shelling hit an electric substation which powered the mine’s elevator at about midday local time – leaving 494 miners stranded underground.
According to International Business Times, all of the men were later rescued over the subsequent hours.
“It comes just over a fortnight since a similar incident trapped 300 miners,” the news site reported.
“The worst tragedy to hit the mine was in 2007 when 101 miners were killed in a methane explosion.”