The drama unfolded shortly before midnight when officers responded to reports of a disturbance at the center, located off 8th Avenue South near S. Thistle Street, said Seattle police spokeswoman Renee Witt.
Arriving at the scene, officers found that "abundant alcohol" was being served inside, and several of the celebrants had begun fighting, Witt said.
But when officers tried to break up the fighting, they were attacked by the crowd. The officers called for urgent backup, and a city-wide call went out for assistance.
King County sheriff's deputies also responded and helped break up the melee. Five officers were assaulted during the mayhem, and two of them received minor injuries.
The community center was evacuated, and the crowd was dispersed. Two suspects were arrested and booked into the King County Jail for investigation of assault, Witt said.