On Monday, May 28th, 2018, at approximately 1110 hours, St. Leonard Volunteers were alerted to a house fire in the 4000 block of Sparkleberry Court in Prince Frederick. Initial reports claimed an explosion was heard and a fire was visible. Chief 7, Chief 7A, Engine 72, Tanker 7, and Ambulance 77 immediately responded. 1st arriving units from Prince Frederick found a single family home fully involved. Chief 2B established command and exterior operations only were performed. In addition upon arrival, the two occupants inside the home at the time of dispatch were found outside at a neighbor’s driveway. The pair from inside the house were conscious, alert and breathing. Helicopters were initially called for transport, but not available due to weather, and both were transported by ground to MedStar. At this time it appears a possible explosion took place, but the official cause of the fire is under investigation by the Maryland State Fire Marshals Office. A total of 60 firefighters assisted with the call, including local mutual aid units from inside and outside of Calvert County. The home and vehicles on the property were destroyed, however, other structures on the property were threatened but ultimately saved during the incident.