CHICAGO (AP) — The upbeat mood in a busy Chicago neighborhood known for its restaurants and nightlife quickly turned into horror late Wednesday as shots were fired at a crowd from a fast-moving vehicle, killing four people.

Eighteen people were shot and four killed in a drive-by shooting outside a restaurant in Chicago’s River North neighborhood late Wednesday, authorities confirmed Thursday. The shooting occurred following an album release party at Artis Restaurant and Lounge for rapper Mello Buckzz.

Gunfire from a passing car ripped into a crowd of partygoers in the River North neighborhood, the police said.