(CNN) -- Residents of a Corpus Christi, Texas, neighborhood had the kind of wake-up call no homeowner wants to get.
An early morning explosion Friday shook the area, sparking a fire that rushed through the neighborhood. In the end, three homes were flattened and about 70 others were damaged, the Red Cross told CNN affiliate KIII.
Two people injured were in critical condition Saturday night. They were first taken to a local hospital and then flown to the burn unit at San Antonio's Brooke Army Medical Center, according to the Corpus Christi Fire Department.
KIII news anchors, in the studio nearly two miles away from the blast site, were in the middle of their live morning newscast Friday when they -- and their viewers -- heard a loud boom. The room appeared to shake slightly.
Eryk Phillips lives in the home behind the blast site.
"I woke up and my ears were ringing," Phillips told KIII. When his hearing started to come back, he said, "I could hear sirens, car alarms going off and all that... and I'm thinking, 'Wow, am I going to die?'"
Phillips' home is littered with glass and insulation. Part of the ceiling is peeled away.
He is among 34 people evacuated.
The fire department believes the cause was probably a natural gas leak inside a home. But state and local investigators are on the scene digging through rubble to determine.