SATV 14 April, Kathmandu: Six people were injured and at least 24 homes damaged after a two-story house exploded on Sunday in Austin, the capital city of the U.S. state of Texas, authorities said.

When firefighters arrived at the neighborhood in northwest Austin, they found the house was leveled to the ground and a neighboring house suffered "severe collapse damage," said Wayne Parrish, division chief of Austin Fire Department.

Among the injured, two are in critical condition, while two firefighters were treated for minor injuries, said Captain Shannon Koesterer of Austin-Travis County EMS.

The cause of the blast remains unknown. Although the neighborhood lacks underground gas lines, the newly constructed home that exploded did have propane tanks, local media reported.

An investigation is underway.