Two people were killed and two others critically injured in a shooting at a Chicago hospital on Monday, and among the dead was the gunman who started shooting in the parking lot and then burst into the medical facility and opened fire, according to local media.

The shooting took place at Mercy Hospital in Chicago city's South Side. Police have secured the hospital and patients are safe, the hospital said Monday afternoon local time.

Eyewitnesses told reporters the shooting began in the parking lot before moving into a clinic area inside the hospital.

Police have not commented on a possible motive for the shooting.

(REUTERS)