A fire damaged the Hope Community Church, just east of Andover near 21st and I-35, Wednesday morning.
No one was hurt. A pre-school connected to the church was evacuated.
Investigators say construction workers accidentally started the fire while doing welding on an addition to the building.
An eyewitness says a spark flew up and caught the back of the church on fire. The building filled with smoke.
Damage is estimated at around $45,000.
People were allowed back inside the church, but firefighters say the building will smell like smoke for awhile. The church will hold its normal Wednesday night service as scheduled.