Assault on Precint 13 (1976) John Carpenter

When a team of heavily armed LAPD officers ambush and kill six members of a local gang, the gang's warlords swear a blood oath of revenge against the police and the citizens of Los Angeles. A newly promoted officer is assigned to take charge of a decommissioned police precinct during the last few hours before it is permanently closed. A prison bus arrives at the precinct seeking medical help for one of three men being transported to the state penitentiary. Across town, the warlords drive around looking for people to kill. One of the warlords fatally shoots a little girl. The girl's father pursues and kills the warlord before other gang members chase him into the decommissioned police precinct. The gang members cut off the telephone n electricity lines n goes out on a rampage shooting violently but at the same time making sure that they don't attract attention.