"They were talking. There was hugging and high-fiving. It was unbelievable," Mr. Lyons said. He has heard a refrain from gang members: Red (the Bloods) and blue (the Crips) make green (money).
Gangs that were once bloody rivals now are cooperating to wring profits from the sale of illegal drugs and weapons, law-enforcement officials and gang experts say. In some cases, gangs that investigators believed to be sworn enemies share neighborhoods and strike business deals. The collaboration even crosses racial lines, remarkable in a gang world where racial divisions are sharp and clashes are often racially motivated.