Seven men were indicted in Charlotte Wednesday for allegedly conspiring to distribute a potent form of heroin. WFAE's Julie Rose reports: Six of the seven men named in the indictment are illegal immigrants from Mexico. On June 30th, the Drug Enforcement Administration searched two addresses - one in Charlotte and the other in Rock Hill - where it seized $20,000 and nearly a kilogram of so-called black tar heroin. It's a black, sticky version of heroin made from poppies in Mexico. DEA spokesman Mike Sanders says the drug is most common in areas with large Mexican immigrant populations: "It comes over in the pockets of illegal immigrants that come to work different jobs. So we see it in the South, the West and along the Southwest border," says Sanders. Earlier this year, the U.S. Department of Justice identified Charlotte as a key distribution point for Mexican drug traffickers selling cocaine, marijuana, meth, and heroin. That's partly because Charlotte has one of the country's fastest growing immigrant populations. This week's indictment is at least the fourth black-tar heroin network in Charlotte to be shut down in the past two years.