While firefighters were on their way to the house, the Fire Department was alerted that people were possibly trapped on the upper level, said Lansing Assistant Fire Chief Jim Baird. Firefighters immediately found the two and paramedics tried to revive them on the scene, he said.

"The gentleman who lived in the first-floor apartment was the one who woke up, smelled smoke, tried to go up to the second floor and got no response," Baird said.

The man then ran outside and called the Fire Department. There was no one else in the house, he said. Firefighters had the blaze under control in five minutes, Fire Chief Dan Gregorovic said.

Autopsies were scheduled for Saturday, but it appeared the mother and son died of smoke inhalation, according to the Cook County medical examiner's office.

The house, sandwiched between a recording studio and a vacant house, had significant damage inside on both floors.

Several boarded-up and vacant houses are on the surrounding streets, and two neighbors said they had never seen the mother or son.

"[The neighborhood] was residential, but now a lot of it is business. I'm actually one of the only homes left," said Ken Komorowski, who lives on adjacent Bernice Avenue.