Police say a gunman who barricaded himself with hostages inside a South Florida apartment complex killed six people before being shot to death by a police commando team.

Sgt. Eddie Rodriguez says the standoff began around 6:30 pm yesterday in a five-story building in Hialeah, north of Miami.

He said police discovered two people shot to death in the hallway in front of one apartment, and three more in a unit on another floor.

Another man was killed across the street when the gunman allegedly spotted him and took aim.

Rodriguez says the two hostages the man took were unharmed. Before the shootout, police communicated briefly with the gunman.

Neighbours say the gunman lived in the building, but police wouldn't confirm that or give details on his identity or possible motive.