Four killed, including gunman and police officer, in shooting at Chicago hospital

A gunman at a Chicago hospital killed a police officer and two others before dying in the shooting, which sent doctors and patients streaming out of the facility, officials said.

The gunman opened fire in the parking lot outside the hospital before bursting into a lobby at the facility and opening fire there as well, witnesses told local television stations.

A police officer, Samuel Jimenez, died in the attack, a police spokesman said on Twitter. The gunman also died, the Chicago Fire Department said on Twitter.

Officials had said two other people were also struck by gunfire, and an investigator at the Cook County Medical Examiner's Office later said those two people also died.

Police cars and ambulances swarmed the hospital after the shooting as officers searched the medical facility.

Police have not commented on a possible motive.

Sue Jimenez, the manager of Kozy's Cyclery bike shop near the hospital, said she heard multiple gunshots separated by pauses. At one point, she heard five shots in quick succession, she said, but the shooting stopped after police arrived.