The LAPD confiscated 5000lbs of illegal fireworks in a residential neighborhood, and without warning decided to blow them up in the neighborhood, sending at least 17 people to the hospital and doing untold damage to nearby houses. After releasing a statement explaining they did so because they thought the explosives were too dangerous to move, they backtracked and released another statement claiming they didn't know why they exploded.
Immunity means the injured parties cannot sue the LAPD for SETTING OFF A HUGE BOMB IN THEIR NEIGHBORHOOD WITHOUT WARNING OR SAFEGUARDS!
Update: it now seems from reports it wasn't the fireworks they detonated in the neighborhood, but was 240 IEDs made with unknown (high?) explosives.