A fourth person has now been charged in last weekend’s riverfront brawl in Montgomery.

Police said Mary Todd, 21, is charged with third-degree assault. She surrendered to authorities on Thursday and is being held in Montgomery’s Municipal Jail.

Todd is charged in the assault on Harriott II Co-Captain Dameion Pickett. Todd was among the group on a pontoon boat whose owner and occupants refused to move while the Harriott II was trying to dock Saturday evening.

Previously charged from the pontoon boat are: Richard Roberts, 48, two counts of third-degree assault; Allen Todd, 23, one count of third-degree assault, and Zachery “Chase” Shipman, 25, one count of third-degree assault.

All charges are misdemeanors and all three had been booked by Wednesday. The attorney for the defendants, Darron Hendley, said Thursday it would be premature to comment.

The victims in the case are riverboat Pickett and a 16-year-old deckhand-in-training.

Police reports obtained by AL.com Thursday said Pickett and the teen sustained bruised ribs and Pickett had knots on his head. Both received treatment at hospitals.

Montgomery police Chief Darryl Albert earlier this week said 13 people were initially detained Saturday night and all released pending the ongoing investigation.

“As Chief Albert has stated, this is truly an active ongoing investigation and more arrests are to follow as investigators methodically comb through hundreds of submitted video,’’ said Maj. Saba Coleman. “Todd’s charge is a direct result of this active ongoing investigation.”