A large explosion that was heard Saturday near Smuggler Mountain in Pitkin County was related to normal mining activity, officials say. 

Shortly after 9 a.m. officials received numerous calls reporting hearing a large explosion near the base of Smuggler Mountain. Some callers reported seeing small flames and smoke, according to a news release. 

First responders were promptly dispatched to the area and found no evidence of flames or damage. 

Officials searched around the area and spoke to several witnesses, who directed them to search the Smuggler Mine property, Aspen Fire Protection District officials said. 

After investigating the historic mine area, on the northern edge of Aspen, officials believe the explosion was related to normal mining operations.

There was no evidence of damage or injuries reported to authorities, but an the investigation into the explosion is ongoing.