Aerial view of Highland Park 4th of July parade shooting, manhunt for the Rooftop shooter

A mass shooting at an Independence Day parade Monday in a suburb outside Chicago, Illinois, left at least six people dead, wounded about two dozen others and has sparked an extensive manhunt for an unidentified gunman, authorities said.

Firearm evidence was found on the rooftop of a business in Highland Park, police commander Chris O'Neill said. The firearm was a "high-powered rifle" and the attack on parade attendees appeared to be "random" and "intentional," said Christopher Covelli, spokesman for the Lake County Major Crime Task Force.

Authorities described the suspect as a white man between 18-20 years old with a small build, long black hair and wearing a T-shirt. They described the suspect as "armed and dangerous" and advised people to shelter in place.
A total of 31 people were transported to two hospitals, according to NorthShore University Health System spokesperson Jim Anthony. The vast majority had gunshot wounds, while other injuries were caused in the chaos after the shooting, he said.

The shooting in Highland Park, about 25 miles north of Chicago, caused hundreds of parade attendees to flee and triggered a large police response of local, state and federal officers, including the FBI.

The Chicago Police Department dispatched a helicopter and other officers in the manhunt, officials said.