The long investigation started in September 2012, when a driver of a car was shot on Highway 101 in Belmont. Then there was one murder after another as the gangs began feuding.
"Operation Sunny Day" took 18 months. The Sheriff's Department and police from every city on the peninsula were involved. They served 80 search warrants, targeting three East Palo Alto gangs called The Taliban, De Vill and Sac Street. The grand jury took two months to review the case ? the longest a panel has ever deliberated in San Mateo County history. Sixteen reported gang members were indicted.
"There are four separate murders that have been charged here. There are two separate attempted murders. There are countless other crimes of drug trafficking, witness dissuasion," said San Mateo County District Attorney Steve Wagstaffe.
Wagstaffe said the gangs committed crimes not only in East Palo Alto, but all over the peninsula. Residents we spoke with were relieved that just maybe the violence will stop.
"Anything that'll help clean up the community up. I mean, because it's had a black eye for a long time," said one resident we spoke to.
"You don't need gangs anywhere. Tell them to get a job!" said another resident.
Alberdia Snowden's 16-year-old son was shot to death in the 1990's. His killer was never found. She told us, "At least they're finding some of these murderers who are taking out these little kids. They are finding them."
Police named the operation "Sunny Day" because of its significance to gang members.
Wagstaffe explained, "When a murder that they had orchestrated, that they had directed, was successfully carried out, their code word for it was 'Sunny Day.'"
For San Mateo County prosecutors and police, this was a sunny day.