At least three people were killed by a man who went on a "murderous rampage" in Chicago and nearby Evanston on Saturday, police in Chicago said.
Several more people were injured by the gunman, who was also killed after a shootout with police, Chicago police Supt. David O'Neal Brown,said at a news conference late Saturday. He said no officers were injured.
Brown identified the gunman as Jason Nightengale, 32, and said investigators had no information about a possible motive for the killings.
He later said on Twitter that a "violent criminal and his murderous rampage was stopped."
Brown said the killing spree began when the gunman fatally shot a 30-year-old man as he was sitting inside a car in a parking garage in the Hyde Park neighborhood of Chicago at about 1:50 p.m. local time (2:50 p.m. ET) Saturday.
The University of Chicago confirmed on Twitter that the victim was "a current student."
About 10 minutes later, Brown said, the gunman killed a security guard in a nearby apartment building before shooting a 77-year-old woman in the head as she was retrieving her mail. Brown said the woman was in critical condition.
After stealing a red Toyota at gunpoint, the gunman shot a 20-year-old man while robbing a convenience story in the city's South Side at 3 p.m., Brown said.
The man, who died after being taken to the city's Christ Hospital, was a "random victim," Brown said.
An 81-year-old woman was also in critical condition after she suffered "gunshot wounds to her back and to the neck, fired from the offender's weapon," he said.
A 15-year-old was also in critical condition after having been shot an hour later in the passenger seat of a car being driven by her mother, Brown said, adding that the gunman later returned to scene, where he fired shots at police officers.
After fleeing to Evanston, just north of Chicago, the gunman took a woman hostage before shooting her in the head, Brown said.
Evanston police — who had arrived in response to a call from the public — engaged in a shootout with Nightengale, who was pronounced dead at a hospital in Evanston, Evanston Police Chief Demitrous Cook told NBC Chicago.
