Firefighters remained on the scene of the fire in the city's Homan Square neighborhood.
SEE ALSO | Highland, Ind. Meijer fires likely set as distraction for shoplifters, police say
Video shows the massive blaze that went up on West Lexington Street Sunday.
Investigators said a woman in her 60s and two children were at the hospital being checked out.
RELATED | Chicago Fire Department shares what high-rise residents should never do if there's a fire
They're now investigating the cause.
Authorities did not provide further information about the incident.