CHICAGO (CBS) — Three people were killed, and four others were injured, in separate fires in Chicago and Northwest Indiana over the weekend.

The first deadly blaze broke out Saturday night in Northwest Indiana. Firefighters pulled two boys, ages 1 and 3, from a window of their burning home in the 2200 block of Wayne Street in Lake Station, Ind.

But rescuers, including neighbors who came running with sledgehammers and other tools, could not reach the boys’ 29-year-old mother, who just two hours earlier hosted a birthday party for her sons. Her body was found about four feet from the front door, a neighbor said.

Family identified the victim who perished as Jennifer Teel. Her body was found five feet from the front door.

Jennifer Teel died in a Saturday night fire in Lake Station, Ind. (courtesy family)

“Knowing that she was literally within arm’s reach, God, I don’t even know what to say,” neighbor Lorri Phillippe said.

Teel’s aunt left flowers from family members outside the home.

“People were trying to get to her, but the flames were too strong,” said Tom Duering, who lives next door. “I used to haul hazardous material, so I’ve seen some bad fires, but I’ve never seen a fire so intense.”

Teel was pronounced dead.

The toddlers — identified by friends as 1-year-old Landon Teel and 3-year-old Andrew Collins — were taken to a local hospital and later airlifted to University of Chicago Comer Children’s Hospital. One neighbor claimed the younger boy looked like “he was going to make it” but said his older brother had burns over much of his body.

Back in Chicago on Saturday, an 85-year-old man died when a fire broke out in his third-floor apartment at the Commonwealth Apartments seniors’ residence, at 2757 N. Pine Grove Ave. on the cusp of the Lincoln Park and East Lakeview neighborhoods.

Theodore Walton was initially believed to be 50 to 60 years old when he was taken to Advocate Illinois Masonic Medical Center, but he was later found to be much older. His body was burned so severely that it was hard to determine his age, fire officials said.

Walton was later transferred to Loyola University Medical Center in Maywood, which has a burn unit, and he was pronounced dead there at 6:37 a.m. Sunday, according to the Cook County Medical Examiner’s office.

Neighbors at the 1920s-era high-rise at Pine Grove Avenue and Diversey Parkway said Walton lived alone, was hearing impaired and used and electronic wheelchair.

Across town in the Chatham neighborhood Sunday night, man was killed in a fire at his home. The fire broke out around 9:40 p.m. at 212 E. 83rd St., according to the Fire Department.

The man is identified as Leslie Jones, 52. He was pronounced dead at Jackson Park Hispital nad Medical Center at 10:35 p.m. Sunday, according to the Medical Examiner’s office.

Paramedics initially took Jones in critical condition to the hospital.

Also in Chatham a few hours earlier, a vacant house exploded Sunday night, startling neighbors and raining glass and debris across the area. No injuries were reported. The one and a half-story brick home in the 600 block of East 87th Street apparently filled with natural gas and exploded at about 5:20 p.m., Fire Media Affairs Director Larry Langford said.

“I was working on my laptop when all the sudden there was a boom! And my whole house shook,” said neighbor Eurydice Decuir. “It sounded like a plane crashed,” she said. Two other fires erupted on the South Side early Sunday.

Two adults were in critical condition due to smoke inhalation after a home caught fire early Sunday on the 10600 block of South Whipple Street. And a fire in the Canaryville neighborhood damaged a vacant building in the 500 block of West 46th Street as well as two neighboring buildings that were occupied — leaving about 10 people without homes.

Serious fires and explosions continued to make headlines Monday morning. One person was injured around 9:30 a.m., when a building exploded at 8734 N. Kimball Ave. in Skokie, just south of busy Dempster Street.

The Sun-Times Media Wire contributed to this report.