AUSTIN, Texas — Six people are injured, including two in critical condition, after a house explosion in northwest Austin on Sunday morning. One house collapsed in the explosion, while another partially collapsed and at least 24 others were damaged.

The incident happened around 11:23 a.m. at 10412 Double Spur Loop, near Spicewood Springs Road and U.S. 183, AFD said. AFD had incorrectly reported the address as Yaupon Drive earlier.

The explosion caused the two-story house to collapse and caused the neighboring house to partially collapse. At least 24 other homes were damaged, including homes on Spicewood Mesa and Pantera Ridge streets.

One person was located in the rubble of the house and taken by Austin-Travis County EMS medics in a critical condition. Another was taken from the house in serious condition, but stable, ATCEMS said.

A third person was pulled from the debris at the neighboring house after “advanced extrication efforts” and was also in a critical condition.

ATCEMS said a fourth person had minor injuries from the explosion. Two firefighters were also injured responding to the explosion, with one of those firefighters taken to the hospital with minor injuries.

Firefighters arriving on the scene put out a vehicle fire, and crews also extinguished small spots of fire within the collapsed debris.

As of around 2:30 p.m., authorities were waiting on excavators to arrive and remove debris. It is believed all victims have been accounted for.

Emergency officials are still investigating the source of the explosion. The Texas Gas Service confirmed the house did not have natural gas service but did have propane. The explosion was heard as far north as Georgetown.

Authorities have closed a large area near the home, while nearby residents have voluntarily evacuated the area. Most will be able to return to their homes on Saturday night, but Red Cross is on the scene to assist families from at least two homes who will be displaced.

Damage to neighboring homes includes garage doors and windows blown out from the explosion.

As of around 12:30 p.m., power was out in the area due to power lines damaged in the explosion. Electricity has now been restored to all homes where it is safe to do so.

A neighbor told KVUE the house had recently been purchased.

Authorities say the explosion was an isolated incident and there is no indication there will be a criminal investigation. The Travis County fire marshal will lead the investigation to determine the cause.