A man is in custody in Bridgeview after allegedly stealing a police vehicle from Bedford Park and later a U.S. Postal Service truck, causing a crash that left three people injured Wednesday.

The suspect took a police squad car after being arrested for disorderly conduct, which he drove toward the Chicago Ridge and Oak Lawn area before it “got stuck or became disabled,” said Bridgeview spokesperson Ray Hanania in an email.

The suspect allegedly exited the vehicle and, seeing a postal truck occupied by a postal worker, forcibly took it and drove north on Roberts Road, Hanania said. He then crashed into the vehicle with the family of three inside.

The mother in that car was at Northwestern University Medical Center Wednesday, and the children, ages 4 and 7, at Comer Children’s Hospital in Chicago and Advocate Christ Medical Center in Oak Lawn, Hanania said.

“One is in very serious condition, I was told,” Hanania said.

The section of Roberts Road between 79th Street and 87th Street was closed in both directions Wednesday night as police investigated, Hanania said.

Breanna Cousins said she was working at Fasano’s Pizza on Roberts Road near 83rd Place when the crash happened.

“I had seen a bunch of police cars heading that direction, because they go right down Roberts,” Cousins said Thursday. “We’re just a couple of blocks down, so that obviously piqued my curiosity.”

Cousins said when she went outside to see what was going on, she saw multiple ambulances, including one being followed by an undercover squad car. She said restaurant customers and neighborhood social media accounts informed her about the stolen mail truck, which was “definitely out of the ordinary.”

However, she said it’s not uncommon to see crashes on the long stretch of road that extends through Bedford Park, Justice, Bridgeview and Hickory Hills.

“I’ve definitely seen a bunch of people speeding down Roberts,” Cousins said. “There’s been a couple instances on 79th and Roberts where people are speeding and they crash into each other, but the mail truck thing really threw it off.”

Police would not name the people injured or the suspect Thursday, as charges have not yet been filed.

ostevens@chicagotribune.com