CHICAGO (CBS) — A car chase that ended Thursday in west suburban Countryside prompted a soft lockdown at Lyons Township High School.

The school’s North Campus at 100 S. Brainard Ave. in La Grange, and the South Campus at 4900 S. Willow Springs Rd. in Western Springs, were on soft lockdown, according to a safety alert posted on District 204’s website at 12:55 p.m.

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A robbery in Chicago prompted a car chase that ended in Countryside, according to the alert. Three people were taken into custody, but a fourth fled the scene.

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“We do not believe that our students or staff are in danger, but as a precautionary measure, we will remain on soft lockdown until given the all-clear from local police,” the district alert said.

A soft lockdown means no outdoor student activities will take place, and building access from the outside is restricted. Students remain in their classrooms and movement within the building is normal.

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