A fourth teenager has been charged in connection with the mass shooting on Danzig Street in July, which left two people dead and 23 others injured.
The latest arrest took place Tuesday, when a 16-year-old boy was charged with three gun offences, including use of a firearm to commit an indictable offence, and one count of threatening death.
The July 16 gunfire at a Scarborough public-housing complex erupted during a confrontation between members of the Malvern Crew and the Galloway Boys, notorious Scarborough street gangs, homicide detectives have said.
The slayings marked the worst mass shooting in Toronto's history.
One of the dead was 14-year-old Shyanne Charles of Toronto, the oldest of four siblings, an accomplished student and keen athlete. The other was Joshua Yasay, 23, a basketball-loving Ajax resident and aspiring police officer.
Last month, a 17-year-old boy was charged with two counts of second-degree murder, 22 counts of aggravated assault and one count each of attempted murder and recklessly discharging a firearm.
Nineteen-year-old Nahom Tsegazab, who was accused earlier this year of recklessly discharge of a firearm, later had the charges upgraded and now faces the same package of charges as the 17-year-old.
The first to be charged was Shaquan Mesquito, 18, who stands accused of two counts of first-degree murder, one of attempted murder and 23 counts of aggravated assault.
Neither of the two juveniles can be identified, under the Youth Criminal Justice Act.
Investigators say the violence was sparked by a snub after the Danzig Street barbecue was visited by rival members of the two gangs.