The State Fire Marshal’s Office is today trying to determine what sparked a house fire in Salisbury Monday night.

Firemen from Salisbury were called to the home on Springfield Circle just after 7 p.m. when neighbors called 9-1-1 for reports of an explosion. Firemen say the sound they heard was probably the back porch collapsing.

There were no injuries in last night’s fire. Damage has been estimated at $100,000.