Sweeping police raids netted indictments against 120 alleged gang members in the Bronx Wednesday, according to law enforcement officials.

Around 700 NYPD officers and federal agents conducted the raids, U.S. Attorney Preet Bharara said at a news conference. NYPD Commissioner Bill Bratton and other officials were also present at the briefing.

Authorities identified two rival gangs targeted in the raids, the 2 Fly Y-Gs and Big Money Bosses. The charges involve drug dealing, firearms, racketeering and eight killings -- including the death of a 15-year-old boy and the 2009 death of a 92-year-old grandmother.

The two gangs have allegedly been battling one another for at least a decade, according to investigators.

Bharara said the raids led to the largest gang takedown in the city's history.

Officials said the investigation focused on gang-related activity in the Eastchester Garden and Soundview neighborhoods, along with several other public housing complexes. 

Bharara said both gangs were dismantled from the top down and that both operated in a similar fashion by storing guns and drugs inside playgrounds at NYCHA facilities.

Multiple federal law enforcement agencies participated in the investigation, which officials said had been underway for around 18 months.

Bharara said the two gangs often took to social media to recruit new members. They allegedly posted gang-initiation videos which depicted beatings. 

During the course of the investigation, officials secured over 100 warrants for various Facebook, Twitter and Instagram accounts belonging to the alleged gang members.

Some of the alleged gang members were already in prison during the raids. Officials say they have been transferred from state to federal custody.