SEATTLE -- Two Seattle police officers were attacked during a large fight on a cruise ship docked in Seattle early Sunday morning.

The officers were attacked by two sisters who were part of a group of people blocking the gangway of an Argosy cruise boat moored at a pier in the 1100 block of Alaskan Way.

A Seattle Police Department spokesman said there was a large fight going on aboard the ship at around 1:30 a.m. Sunday.

When responding officers arrived, a group of people tried to prevent the police from boarding and breaking up the fight.

According to the police report, while moving the group off the gangway, a woman assaulted an officer by jumping on his back, grabbing his throat and scratching him.

A second woman assaulted another officer, scratching him on the throat.

Both women were arrested and booked into the King County Jail on charges of assaulting an officer.

Both police officers were treated for their wounds at the precinct.

Witnesses told police that the incident began when four women started fighting on board the ship and it escalated from there.

Police said there were more than 100 people on the dock when they arrived, some of them in verbal disturbances with one another.