Debris from the explosion hangs from the trees and is scattered across the street in the Sun Prairie neighborhood, about 15 miles (25 kilometers) northeast of Madison.
Residents were evacuated the neighborhood following the explosion about 3:30 a.m. Tuesday.
Several residents reported a strong odor of natural gas, and utility We Energies has shut off gas service in the area.
There's no immediate word on the conditions of the injured.
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