VICTORIA, Texas -

Investigators are still looking into what caused an explosion that leveled a home and killed a young mother in Victoria.

"In my 20-plus years of experience as an investigator, I've never seen a scene like this," said Victoria County Fire Marshal Ronald Pray.

The explosion happened Wednesday morning in the 200 block of Oak Colony Drive.

When crews arrived they found the body of 26-year-old Haley Singer. Her baby girl was found under debris, alive.

"The baby, I believe, was in a Pack n' Go play pen and she was tangled up in there," Pray said. "Then it had a mattress on top of that and there was a bunch of debris on top of that."

Investigators spent all day Thursday taking pictures of the scene, trying to figure out what caused an explosion so powerful, it also damaged 19 other homes. All sorts of debris can be seen in trees and scattered throughout the cul-de-sac.

"This is a catastrophic event that occurred and not something that happens everyday," Pray said.

He says residents of all but one of the damaged homes can continue staying in their homes. The investigation into what caused the explosion could take days, even weeks.

Singer's baby girl was transported to a hospital in San Antonio. She is expected to be OK.