Updated 03/14/14 – 1:25 p.m.

CHICAGO (CBS) — An investigation is underway after an off-duty Chicago police officer was killed early Friday when a speeding van slammed into his car while the driver tried to evade a suburban squad car.

CBS 2’s Mike Puccinelli reports the chase started in south suburban Calumet Park, and witnesses said the vehicles involved hit speeds of more than 100 mph. It ended about six miles away, at the top of an exit ramp from the Dan Ryan Expressway on the South Side.

Police began pursuing a white van in Calumet Park around 12:45 a.m. Friday. The chase continued on I-57 and the Dan Ryan Expressway until the female driver exited the expressway at 87th Street, and crashed into Chicago Police Officer David Harris’ Lexus at 87th and Lafayette.

Chicago Police Officer David Harris (Chicago Police Dept.)

Chicago Police Officer David Harris (Chicago Police Dept.)

Harris, 42, was just finishing his shift and was on his way home at the time, authorities said. He was still in uniform when emergency crews found him.

The Lexus was crushed by the impact, reduced to a mangled mess of metal. Harris, a 10-year veteran of the department, died at the scene.

“Last night’s traffic crash, which killed a Chicago Police Officer, is a terrible tragedy,” said Chicago Police Superintendent Garry McCarthy. “He dedicated his life to protecting our residents and communities, and our thoughts and prayers are with his family, friends and colleagues. We ask everyone to respect the privacy of the officer’s family and friends in this difficult time.”

The village attorney for Calumet Park said an investigation is underway into the police pursuit that preceded the fatal collision, CBS 2’s Courtney Gousman reports. The Calumet Park officer who gave chase reportedly had conducted a traffic stop.

Leah Gomillia and Florence Johnson said they got on I-57 at 111th Street and saw the van fleeing police. Gomillia said she sped up to 100 mph to catch up to the van, and saw it was a young woman driving, with a man in the passenger’s seat.

“What was so serious for you to drive that fast and actually just keep running?” Gomillia said. “Eventually you’re going to get caught, because it’s too much traffic out here, period, on the expressway.”

“They should have just stopped, because now somebody’s dead,” Johnson said.

One person was loaded into an ambulance at the scene, but it was unclear if it was the driver who fled from police, or a passenger in the van.

Police officers escorted their colleague’s body to the morgue in a procession of squad cars. They then exited their vehicles to form an honor guard to pay tribute as his body was taken inside. The officer’s name has not yet been released.

Harris, who leaves behind a wife and two children, was described by relatives and admirers as a deeply devoted family man.

“He had a beautiful soul. Everybody loved him,” Willie Austin, an aunt by marriage, told CBS 2.

Austin expressed shock at the suddenness of Harris’ death.

“You get off your job. You’re trying to get home to your family and you end up in a tragic accident,” she said.

Calumet Park police took a man and a woman from the van into custody after the crash. No charges had been filed as of Friday evening.

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