SAN ANTONIO -

Fire investigators are looking into burning trash as a possible cause for Monday’s deadly fire on Old Pearsall Road in Southwest Bexar County, according to officials with knowledge of the investigation.

Officials said numerous witnesses interviewed by law enforcement have said someone was burning trash outside one of the homes that caught fire on Monday.

Roxanne Moreno, 31, and her two boys, Orlean and Daniel, both 1, were killed inside their home after it caught fire. Their home was one of four completely destroyed.

Officials said high winds likely exacerbated the damage, sending embers up into the air that caught other homes on fire.

“It just happened so fast,” said Rita Fonseca, a family member of the victim’s. “It was there one second and completely gone the next.”

It wasn’t immediately made clear Tuesday why Roxanne wasn’t able to get out the house before the fire started.

“We’re not sure why it started, but all we know is that three beautiful people were killed,” said Luis Fonseca, a family member.

A vigil is scheduled to be held at 7 p.m. on Tuesday in front of the Moreno home in honor of the three people who died there.

The Bexar County Fire Marshal’s office would not officially confirm the report when asked on Tuesday afternoon.

However, Bexar County Public Information Officer Laura Jesse issued a statement Tuesday, which read in part: "Our investigators still do not have a conclusive cause of the fire and will continue tomorrow with follow-up on statements they took today from first responders, residents and witnesses. Part of that investigation includes the autopsies."

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