Criminal gangs in the area are increasingly relying on new technology to abet their felonies — coordinating with fellow gang members on Twitter and Facebook, posting videotapes of their exploits on YouTube, and receiving orders through conference calls with bosses in Salvadoran prisons. Gangs in the D.C. area are younger than in past years, and some have strikingly nontraditional configurations: There are girl gangs, gay gangs and gangs that claim to be Muslim in an effort to cover up their activities, according to law enforcement officials.

They may not be as organized as groups from earlier generations — which had clear command structures, dues and initiations — but authorities say these groups are just as dangerous.