Officers were dispatched to the scene shortly before 2 a.m. Thursday after someone called 911 to report seeing a severely injured person on the street.

Before he and the woman were rushed to the University of Chicago Medical Center, the man told officers that the woman had stabbed him before she threw one toddler out the window, Guglielmi said.

Guglielmi said that the positions of the body suggest that a 1-year-old boy was thrown out of the window before the woman jumped herself. He said that it is unclear why she survived, saying that perhaps something broke her fall.

Officers rushed up to the apartment after being directed there by building security and found the body of a 2-year-old boy in a bathtub. He said the boy had suffered severe lacerations and was badly burned by scalding water.

Both children were pronounced dead at Comer Children’s Hospital.

The 70-year-old man was found inside the apartment, bleeding profusely from cuts to his face and body. There were initial reports that the man was the father of the woman, who is believed to be in her 30s, but Guglielmi said Thursday morning that based on the ages of the two and what the man told police, investigators believe he is the woman’s grandfather. Guglielmi also said he did not know if a weapon had been recovered.

Guglielmi said that police have not determined a motive for what appears to be a murder-attempted suicide by the woman. He said there were no calls made to police about any disturbance at the apartment in the hours before the 911 call.