By Michelle Relerford and Alexandra Clark, NBC Chicago
Two toddlers who died in a fire early Saturday morning were left alone with two other young boys when the blaze broke out inside their Chicago apartment on the city's southside, police said.
Family and friends gathered Saturday evening for a vigil to honor 2-year-old Jariah and 3-year-old Jarvis. The boys were alone with a 7-year-old and a 4-year-old when the fire ignited.
Neighbor Tiffany Williams recounted what the boys who escaped told her: "They said they heard the baby crying, beating on the door but they couldn't go back to get her cause they were choking on the smoke."
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Authorities believe a hot plate used for heat sparked the flames, but the cause remains under investigation. When the fire started, a relative helped the two older boys to safety, but Jariah and Jarvis stayed trapped inside the apartment.
A resident who called 911 just before 3:30 a.m. told authorities that young children were trapped inside the burning home in the 6400 block of South Paulina Street in the West Englewood area, Fire Media Affairs Director Larry Langford said. When firefighters arrived, the fire had blown out a window, with the open air feeding the flames.
?Everybody concentrated and made a frantic search to find them,? Langford said.
But ?extensive? fire made it difficult for firefighters to reach the rear bedroom where the fire started, and where the children were located.
Witnesses said the children's mother was frantic.
"She was going crazy, no one could control her," Williams said.
Firefighters used a saw to cut the bars off a basement window in an attempt to reach the children, but they were unable to rescue the toddlers in time. They later found the children's bodies in the three-bedroom apartment on the first floor of the two-story gray stone building.
Fire investigators continue to sort out what caused the fire. They are also talking with the mother, who police said left the four children home alone.
"They said their mother was getting dressed told them to go in their room and go to sleep," said Williams. "They said they were left there alone and they'd been there by themselves for a long time."
The two surviving children were taken into the custody of Illinois Department of Children and Family Services.
Crews have not found any working smoke detectors in the home, Langford said. The Chicago Fire Department canvassed the neighborhood on Saturday, starting at 10 a.m., to pass out smoke alarms and share fire safety information.