``We can thank the Lord this occurred today and not yesterday,'' Wichita Fire Chief Mike Rudd told reporters.
KFDI reported two injuries, one serious and another minor.
The explosion heavily damaged the new addition under construction. It knocked debris into the street and hit houses across the street. The concussion from the blast also damaged windows and doors of nearby homes, Rudd said
About 25 residents near the school were evacuated and taken to a church for shelter, Rudd said. A number of construction workers and school personnel were in the building at the time of the blast.
No one was trapped inside, he said.
Damage to the school was severe enough that some classes will likely have to be moved when students return next week. But Rudd said it was uncertain yet how extensive the damage was to the older parts of the school that were further away from the blast.
In addition to the blown out wall on the east side of the building, the southeast section that was still standing separated from the structure. Fluorescent lighting fixtures dangled from wires.
Heidi Baxter, who works for computer services for the district, was inside the building when the explosion occurred.
``I felt it. The floor shook and the ceiling tiles were coming down,'' she told The Wichita Eagle. ``I didn't realize what had happened until I came outside. It was a big surprise to see how damaged it was.''
Alvin Osborn, head custodian for Marshall Middle School, thanked God school was not session: ``That'd be a heck of a mess.''
