A manhunt has been launched for “multiple shooters” who killed four and injured 18 more when they “fired upon a large group of people,” in Birmingham, Alabama, police said early Sunday.

Police Chief Scott Thurmond said that multiple people pulled up in a vehicle, got out and opened fire before getting back inside the vehicle to flee the scene. A total of 21 people were shot, including the four people killed.

The chief did not release the identities of any suspects, but Thurmond said a…