Johnson was shot in the abdomen and transported with three others to the hospital, while one passed away on the scene from multiple gunshot wounds, according to a Bakersfield Police Department news release.
Police investigation determined that the shooter was a black male in his late teens and possibly accompanied by another black male and a black female in their late teens. The shooter "suddenly brandished a semi-automatic handgun and began to indiscriminately discharge the weapon multiple times into the crowd striking all of the victims," the report stated.
Police said they were called at 12:34 p.m. for a possible assault with a firearm near the intersection of First street and T. The celebration was held at a residence in the 200 block of T street.
Johnson (12-3) has stopped his last five opponents before any entered the second round, and in his most recent fight, on May 15 at the first-ever ShoMMA, knocked out Carl Seumanutafa in 18 seconds.
Johnson was next scheduled to fight at a Strikeforce event on August 15 at the HP Pavilion in San Jose, California. He was in talks to face PRIDE and EliteXC veteran James Thompson.