[1] Newspapers reported[2] that firedamp was ignited by a miner's oil lamp, resulting in the deaths of 109 men and boys.

Accounts vary, but it is believed that either 107[3] or 109[1] coal miners, mostly Polish, Hungarian, and Italian immigrants, were killed on the morning of the explosion.

Seventy-nine of the victims are buried in a mass grave at St. John the Baptist Cemetery.

In the early 2000s, two Pennsylvania Historical & Museum Commission markers and a pair of personalized headstones were added to the site.

The entrance and a memorial to the miners killed in the accident are located behind the Mount Pleasant (PA) Township Municipal Authority building, which was formerly the lamp-house, where miners' safety lamps were stored and distributed.