Small groups of mourners stood in the rain in front of Handlova town hall where the Slovak national flag and a black flag of mourning hung at half mast.
"This tragedy can't be compared to any other in Slovakia's industrial sector," said Rudolf Podoba, the town's mayor.
"Now the top priority is to get the bodies of our late friends out of the mine and say farewell to them," said Podoba, who also spent most of his life underground as a miner.
"The fact that I'm now the mayor of the town doesn't mean anything, my heart beats for mining," said the fourth-generation miner.
Handlova is located 190km from Bratislava, the capital, and many residents are either related to, or know somebody, who works in the lignite or brown coal mine.
"Our son works in the mine, he was supposed to be there yesterday but he took a last-minute day off," said Ladislav Petrik.
The explosion occurred at about 9:30 am [0730 GMT] on Monday as the miners were putting out a fire about 330m underground.
Nine miners who escaped the blast with minor injuries were treated in a hospital and later released.
With a workforce of 4,100, Hornonitrianske Banke Prievidza is Slovakia's top brown coal producer, supplying fuel to the nearby Novaky heating plant.
The mine produces about 2.2 million tonnes of lignite per year and has plans to open new mines in the region after the discovery of deposits of approximately 7.2 million tonnes.