New details have been released on what happened just before a deadly accident in Oak Lawn.

Three people were killed and 11 were were taken to hospitals, two in critical condition, after a multi-vehicle crash just before 4:30 p.m. Sunday.

According to Oak Lawn police,  a witness says Edward Carthans, 81, was first seen driving a Ford pick-up at 95th & Western Ave. He appeared to be slumped over at the wheel of his truck . When asked if he needed assistance, Carthans allegedly said he was OK and drove away.

A short time later, Carthans was involved in a four car crash at 95th St. and Keeler Ave. He fled that scene at a high rate of speed, when he was then involved in the fatal crash on 95th St. and Cicero Ave.

Carthans died at the scene, along with two other people who were stopped at the light. They have been identified as 86-year-old Sister Jean Stickney, and 48-year-old Sister Kab Kyoung Kim of Little Company of Mary Sisters.

This incident is still under investigation.