Police said the 44-year-old man was found unresponsive near the tracks in the 1100 block of Komar Avenue in West Humboldt Park around 9 a.m. Tuesday.
The man has been identified as Roberto Fonseca Jr. He was found about two miles from where he lives, according to police.
An autopsy conducted Wednesday said Fonseca Jr. died of strangulation.
Neighbors said Fonseca Jr. was a kind man, a beloved soccer coach and the father of three girls.
The investigation is ongoing. No other information was provided by police.