UPPER ARLINGTON, Ohio (AP) — A police cruiser that was responding to a robbery report, its lights flashing, collided with a car at an intersection just northeast of Ohio's capital early Friday, killing all six people in the car and injuring an officer, officials said.

Investigators said an officer from the Columbus suburb of Upper Arlington was responding to a reported armed robbery at a fast-food restaurant when the crash occurred around 1:30 a.m. at a large intersection that includes traffic lights. Police said the cruiser's lights were flashing, and they believe the siren also was being used.

The people killed in the other vehicle included a small child. Authorities believe but haven't confirmed that the driver and a woman riding with him were the parents of the other four people, all girls, said Chief Robert Oppenheimer of Perry Township police, who are investigating the crash.

Police believe none of the six was wearing a seatbelt.

"That car was just totaled, and they probably died instantly," Oppenheimer said. Autopsies were planned.

The victims' names and ages were being withheld while authorities notified their relatives.

The officer, who had been traveling alone, was being treated for a serious head injury at a hospital but was in stable condition, said Jason Pappas, head of the local police union.

Oppenheimer said a computer expert on Monday will help pull speed and braking data and dash-camera video from the cruiser that could explain more about how the crash occurred.

"We just don't know anything about the condition of the intersection at the time of the accident," he said. "We've had no witnesses step forward. The only thing we have is the driver of the cruiser, and he's in the hospital, and we're unable to talk to him at this time."

Oppenheimer said investigators hadn't interviewed the officer by late Friday morning but expected to do so later with his attorney present.

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