MINNEAPOLIS (WCCO) — Authorities in Wright County say two school buses were hit by gunfire early Tuesday morning.

According to the Wright County Sheriff’s Office, it happened after 2 a.m. at the Stahlke Bus Service facility on County Line Road in Delano.

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A man was gassing up his SUV at a nearby Holiday Station before the incident. When he left, he noticed a car with a broken headlight following him. When he turned into the Stahlke facility, someone fired several shots at his, leaving bullet holes and breaking windows. The broken glass left a small cut on the driver’s face.

Investigators say the gunfire hit a bus parked nearby, and one bullet went through a garage door and shattered the back window of another bus inside. Authorities say nobody was inside the bus garage, or in either bus that was hit, at the time of the incident.

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(credit: CBS)

Deputies say they recovered four bullet casings on the roadway. They’re still processing the scene Tuesday.

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Authorities say they believe the incident was isolated, and there is not a public safety risk. There have been no arrests, but authorities say the investigation is active and ongoing.