CHICAGO
11/27/2011 02:33 pm ET | Updated Jan 27, 2012

Crystal Lake Plane Crash Kills 4

A businessman, his daughters and a friend were killed in a small plane crash outside of Chicago

An FAA spokesperson told the AP that the pilot, Ray Harris, was operating with "visual flight rules"--or looking the window to see where he was headed. He had not been in touch with air traffic control.

Also on board were his daughters, Ramie and Shey, as well as Chris Backus, one of the girls' boyfriend.

The Chicago Sun-Times reported that the group was headed towards Wheaton College to drop off Ramie at school.

Witnesses described the scene of the crash as "horrific".

The National Transportation Safety Board is investigating the cause of the crash, which could not immediately be determined.

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