“As part of the push to increase uses of civilian drones,” the Wall Street Journal reported last week, nearly 50 companies are developing some 150 different systems, ranging from miniature models to those with wingspans comparable to airliners.” Law enforcement and public safety agencies are a prime target of this industry, which some predict will have $6 billion in U.S. sales by 2016.

Altogether, the drone industry’s lobbying group, Association for Unmanned Vehicle Systems International, claims 507 corporate members in 55 countries. The industry proved its clout in February when Congress mandated the FAA open U.S. airspace to drones starting this year. According to the AUVSI’s annual report, the group was responsible for the legislative language ordering the FAA to expedite the applications of qualified public safety agencies seeking to fly drones weighing less than 4.4 pounds this year. Larger drones will be eligible to fly in U.S. airspace by 2015.

Perhaps the most prominent firm in the U.S. drone market is Vanguard Defense Industries in Texas, which sold a $275,000 drone called the ShadowHawk to the Montgomery County Sheriff’s Office in Texas last year. The company is run by CEO Michael Buscher, a 24-year veteran of U.S. Army Special Operations. In his LinkedIn profile, Buscher says that VDI offers technology “that will dramatically extend U.S. national security capabilities.”

Uniquely among U.S. manufacturers, VDI touts its ability to weaponize drones for local police departments. “If you think weaponized unmanned aerial vehicles (UAVs) are still too new to combat zones for law enforcement to consider them for domestic use, think again,” said the editors of Special Weapons for Military and Police in February:

The Kevlar fuel tank mounted beneath the ShadowHawk allows it to stay in the air long enough to provide complete surveillance of an area and engage suspects with buckshot, tear gas, grenades and less-lethal capabilities.

Vanguard has touted the weaponized ShadowHawk to police departments in Ohio and Illinois, according to emails published online by the hackers collective AntiSec. The group hacked the email account of Richard Garcia, a VDI vice president and a former FBI agent, with the stated goal of causing “embarrassment and disruption” to the company. (VDI says a group of British hackers arrested in England were responsible for the hacking. VDI did not respond to a request for comment.)