ELGIN — Authorities say an Elgin police officer fatally shot a woman armed with a knife along an Interstate 90.

Elgin Police Chief Jeffrey Swoboda says the shooting happened when police tried to pull the woman over for a traffic stop about 12:35 a.m. Monday. Swoboda said officers negotiated with the woman for more than an hour to put the knife down.

Swoboda said officers then saw flames inside the SUV and approached to pull her out. He says one of the officers fired a weapon but the chief didn’t offer details of the encounter.

The woman was pronounced dead at a Hoffman Estates hospital. The Cook County medical examiner’s office identified her as 34-year-old Decynthia S. Clements of Elgin.

Swoboda says Illinois State Police are investigating and the officer is on paid leave.

—Associated Press