MONTROSE, Ga. (AP) — The Georgia Department of Transportation says a crew was on the way to place signs warning of low-visibility on Interstate 16 when cars began crashing in a fiery, 27-vehicle pileup that killed four people.

DOT spokeswoman Jill Goldberg says a call from a 911 operator Wednesday morning saying motorists were complaining about driving conditions prompted the agency to dispatch a crew with caution signs from Dublin, about 10 miles from the crash scene.

Goldberg says less than 30 minutes elapsed between the operator’s call and the pileup. She says the crew had signs loaded into a truck and was en route when the DOT learned of the crash.

The crash happened just after 8 a.m. Wednesday. In addition to those who were killed, nine people were sent to a hospital.