At least six people have been killed and two dozen others injured in a shooting at an Independence Day parade in a Chicago suburb, officials in the US city of Highland Park said, as authorities continue to search for the suspect.

Officials told a news conference on Monday afternoon that six people were killed and 24 taken to hospital, and that a rifle was recovered from the scene.

“Our community was terrorised by an act of violence that has shaken us to our core. Our hearts go out to the families of the victims during this devastating time,” Highland Park Mayor Nancy Rotering told reporters.

President Joe Biden last month signed the widest-ranging gun violence bill passed by Congress in decades, a compromise that showed at once both progress on a long-intractable issue and the deep-seated partisan divide that persists.

Biden on Monday said he and first lady Jill Biden were “shocked by the senseless gun violence that has yet again brought grief to an American community on this Independence Day.” He said he had “surged Federal law enforcement to assist in the urgent search for the shooter, who remains at large at this time.”

Police believe there was only one shooter but warned that he should still be considered armed and dangerous. Several nearby cities canceled events including parades and fireworks, some of them noting that the Highland Park shooter was still at large. Evanston, Deerfield, Skokie, Waukegan and Glencoe canceled events.