Officials are investigating after an explosive device was detonated on a porch early Monday morning in St. Joseph.

Sgt. Wayne Byrom with the St. Joseph Police Department said the Bureau of Alcohol Tobacco Firearms (ATF) is assisting police after an explosion in the 2400 block of Northeast Parkway.

Byrom said officers responded around 3 a.m. after a device was detonated. He said the homeowners were home at the time of the explosion. No injuries were reported. The blast caused extensive damage to the front porch and entryway. Little other information was available.