Updated

New York City is enlisting former gang members as "violence interrupters" to help keep the peace amid a summer uptick in the killings of young people.

The city funds 18 such groups that attack acts of violence like outbreaks of a disease they must keep from spreading.

They hold rallies to stoke outrage over crimes. They hang out in high-crime spots to watch out for trouble. And they step in to mediate fights.

They are part of Democratic Mayor Bill de Blasio's (dih BLAH'-zee-ohz) plan to maintain historically low crime rates while also improving police relations with minority communities.

This year, they're facing a particular challenge: 16 people between the ages of 10 and 18 have been killed in the city, already matching last year's total.