It became clear in 1986 that Edmond and other homegrown dealers couldn't satisfy the demand, and word of the lucrative Washington market spread to Jamaican gangs out of New York and Miami. The Jamaicans were the first vertically integrated black drug-dealing operations to hit the United States. They were capable of importing cocaine, distributing it through wholesale networks, and selling it retail directly to customers through apartments that became known as crack houses. The Jamaicans helped to introduce crack to Washington, but their legacy was gunfire and violence. D.C. police busted Jamaican crack houses and found AR-15 assault rifles
[Brought into DC by the Jamacains from Central/South American countries that the US had given foreign aid (weapons) to?], Glock semiautomatic pistols
[Stolen/Graft from NYPD?], and Mini-Tee Nines
[no idea]— all sophisticated, high-powered weapons that could fire bursts of bullets.
The District government passed one of the strictest gun control laws in the nation in the mid-1970s. Private citizens cannot own or carry a handgun legally. The city issues no permits. There are no exceptions. Moreover, the federal agency charged with regulating guns— the Bureau of Alcohol, Tobacco, and Firearms— is headquartered in the District. But the District's law was impossible to enforce, primarily because there's an arms bazaar at the city's back door. Right across the Potomac River in Virginia, gun control regulations were virtually nonexistent and easily skirted. Any teenager from Washington with folding cash could belly up to a gun store counter, buy an arsenal of high-powered weapons, and cross one of four bridges into the District loaded with guns and ammo. So many handguns came into the capital that the prices went through the floor. Anyone could rent a handgun for a day, buy one for fifty dollars, or trade one for cocaine.
[bullshit]
Edmond's top enforcers, Jerry Millington and James "Tonio" Jones, knew that Michael Frey would retaliate for Brandon Terrell's shooting. They dispatched Greg Royster to a gun shop in Virginia Beach, and he returned with a small cache of semiautomatic weapons and submachine guns.
[I don't see how he could have done this, because GCA-1968 banned interstate sales, and long guns/shotguns were banned by DC so they could not be bought by a resident going into VA. Submachine guns is where they go full retard, because as you stated only certain NFA licensees were selling them]
Jaffe, Harry (2014-04-22). Dream City: Race, Power, and the Decline of Washington, D.C. (Kindle Locations 4115-4117). Argo-Navis. Kindle Edition.