A man fleeing Chicago police after an attempted traffic stop in Austin on Friday led officers on a three-city chase, eventually crashing his vehicle in Oak Park.

The chase began in Austin, but Chicago Police News Affairs on Wednesday was unable to release details about the suspect or reasons why he fled.

According to eyewitness accounts and sources in the Chicago and Oak Park police departments, the man may have been carrying some type of illegal narcotics with him.

Chicago police attempted to pull over Thurman A. Butler, 30, of Northlake at around 1 in the afternoon last Friday.

Butler, according to police, pointed a hand gun at a Chicago gang crimes officer, which instigated the pursuit.

Police tried to pull him over, chasing him through the Austin neighborhood. The high-speed chase ventured into Oak Park and River Forest.

After speeding west up LeMoyne Parkway in northwest Oak Park, Butler reportedly crossed into River Forest, then headed back across Harlem Avenue, where he hit another car traveling northbound. The driver of that car was taken to Loyola Medical Center, where he was reported in good condition.

After reentering Oak Park, Butler, driving a newer model Chevy conversion van, continued east through an alley just south of North Avenue, where the suspect allegedly tossed something out the window.

Chicago police confirmed a witness account that suspected narcotics were recovered after a search of an alley.

Chicago, Oak Park and River Forest officers cornered the van, which had both front tires blown out, at the end of an alley east of the 1200 block of Forest Avenue in Oak Park. Numerous officers rushed in with guns drawn, according to eyewitness and Chicago officers’ accounts. Police busted out a side window and pulled Butler out.

Kerstin Clouser, an Oak Park resident witnessed parts of the chase.

Clouser had just seen her daughter off to attend the Harry Potter events that took place in Oak Park Friday afternoon when she heard sirens.

She said she heard one officer tell another that he’d recovered “a kilo or two” of an unidentified substance. Attempts to determine any charges against Butler from police were unsuccessful.

“There was a van going up [Le Moyne Parkway] at a high rate of speed,” said Clouser. “It was going at least 60 miles an hour, followed by six or seven Chicago police cars.”

Saturday morning, Chicago officers turned Butler over to Oak Park police for processing on numerous traffic violations.

He was charged with aggravated fleeing for not stopping after Oak Park officers attempted to pull him over in the 900 block of North Elmwood Avenue, as well as four counts of attempting to elude police and aggravated reckless driving.

Terry Dean contributed to this article