Updated Friday 4:30 p.m.:
The medical examiner has determined that David Di Paolo committed suicide, according to a statement from the Village of Glencoe.
He suffered a "massive trauma to his head, causing his death," the statement says. It did not explain the source of the trauma.
According to his obituary, Di Paolo was a married father of three.
Original story from Wednesday:
The unconscious man found Thursday by the side of the Metra tracks in Glencoe has died, according to an article in the Chicago Sun-Times.
Glencoe officials identified him as 49-year-old David DiPaolo of Winnetka. He was found at about 6 a.m., breathing but unconscious.
He was pronounced dead on Tuesday, though it is still not clear if he was hit by a train or fell and hit his head, the Sun-Times article says.