CHICAGO (CBS) — A Chicago Police K-9 Unit squad car was among three vehicles involved in a crash Wednesday morning on the Eisenhower Expressway.

The crash happened about 6:20 a.m. in the outbound lanes of I-55 near South Peoria Street, according to Illinois State Police.

One of the vehicles was an unmarked CPD K-9 Unit vehicle, but additional details were not immediately available, police said.

Everyone at the scene refused medical treatment, said Chicago Fire Department Deputy District Chief Michael Del Greco.

As of 6:50 a.m., all lanes of the expressway were open to traffic, police said.

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