Rockford, IL – Fire investigators have determined that a natural gas explosion at 2:24 p.m. Sunday damaged a house at 2906 Marshall St.

How it happened remains undetermined and under a continuing investigation, Rockford Fire Department Investigator Chad Moe said.

No one was home at the time and no one was injured in the explosion.

A fire blew itself out before firefighters arrived, Moe said.

Evidence collected at the house is being examined to determine if the explosion was accidental.

Rockford city building inspectors condemned the house because of structural damage, Moe said. No one is allowed to live in the home unless it is repaired and the condemnation is lifted.