A bloody early October has raised the city’s year-to-date homicide count to 257 — seven more killings than at the same point last year, according to police data.

This year’s increase was fed by a bloodbath Saturday at an illegal Brooklyn gambling hall that left four players dead.

The tally was also boosted by a rampage Oct. 5 in which a vagrant allegedly bludgeoned four homeless men to death in Chinatown.