Police in Virginia are investigating after an explosive device was detonated in Williamsburg. News outlets report the device was found Thursday night in a parking lot. Firefighters and police were called to the scene near Merchants Square at about 5 p.m. for what they thought was a car fire. When they arrived, they discovered the fire was caused by an improvised explosive device. No injuries were reported. The FBI and Virginia State Police are assisting in the investigation.