Updated 3 hours ago An altercation that began at La Jolla Boulevard and Marine Street on Wednesday night ended nearly five miles away near Bonita Cove in Mission Bay when police took a bicyclist into custody after a motorist was knocked out in La Jolla. Police said some members of a large group of bicyclists started beating the man shortly before 8 p.m., eventually knocking him unconscious. At that point, investigators said, some bystanders intervened and the people left on their bikes. Download our NBC 7 mobile app for iOS or Android to get alerts for local breaking news and weather. Officers ended up calling in the aid of a police helicopter to track down the bicyclists, eventually locating them near West Mission Bay Drive and Gleason Road in Mission Bay.