Drones have recreational uses and aid in jobs such as aerial photography, shown here, but their potential for malicious uses has security experts working overtime. (Getty Images)

Earlier this month, two unmanned drones carrying four pounds of plastic explosives targeted Venezuelan President Nicolas Maduro and his party in an assassination attempt during an outdoor event. The military thwarted the attack, intercepting one of the drones; the other crashed into an apartment building two blocks away.

The concert industry, already jolted by mass killings last year at Ariana Grande’s Manchester Arena concert and the shooting at the Route 91 Harvest music festival in Las Vegas, has taken notice, and is employing security experts to examine and counter the threat.

One of them is Michael Downing, who spent 35 years with the Los Angeles Police Department, 10 as deputy chief for counterterrorism for the department’s Special Operations Bureau.  Downing is now chief security officer for Oak View Group and president of OVG subsidiary Prevent Advisors (OVG is also the parent company of VenuesNow).

Downing says he has been warning the industry about the threat of weaponized drones, which have become prevalent outside the U.S., for more than a year now.

“The drone threat is continuing to evolve,” said Downing, also pointing to recent terrorist threats to stadiums in Spain and missives from al-Qaida and the Islamic State group about stepping up drone warfare. “Expect it to arrive in the U.S. in the near future.”

There are 2 million drones in the United States, the vast majority for recreational use, but unmanned aerial systems are also employed by local law enforcement and fire departments, as well as S.W.A.T. teams for search and rescue along with hostage situations. 

Strategies for aggressively countering threats from potentially malicious drones are effectively grounded by legislation that prevents the interception of any drones in federal air space except by the departments of Defense and Energy, the National Security Agency and the Secret Service. 

Even then, they are allowed only to “monitor and detect” a drone for suspicion of four federal crimes: air sabotage, computer hacking, pen register (tracking the phone numbers of outgoing calls) or wiretapping. Local law enforcement can interdict, but only if it can prove an imminent threat to life.

Downing is supporting a bipartisan bill that the Senate Homeland Security and Government Affairs Committee approved in June that gives both the Homeland Security and Justice departments limited legal authorization to counter threats posed by malicious drones. In the House, Texas Republican Michael McCaul, chairman of the Homeland Security Committee, and Ohio Republican Steve Chabot, a member of the Judiciary Committee, introduced a companion bill.

It remains illegal to down an aircraft in national air space.

According to Downing, these bills would allow the testing and evaluation of technologies specifically designed to detect, track and mitigate systems that may pose a threat.

Downing has been working with San Diego-based Citadel Defense Co., which specializes in “real time threat protection” and has developed a technology that involves a virtual boundary a mile in radius that will repel invading drones and send them back to the base station pilot. Downing points out recent incidents of recreational drones crashing into the Los Angeles Memorial Coliseum and San Diego’s Petco Park as well as hitting a Black Hawk helicopter on the East Coast as examples of threats not necessarily from terrorists or organized crime.

The Citadel Defense system, designed by CEO Daniel Magy, can also be configured to detect legitimate “white label” drones, the kind being employed, for example, by law enforcement agencies.

Said Magy: “Our automated modular defense solution uses proprietary machine learning algorithms to detect and engage unwanted drones.”

Downing also tests stadium, arena and large-scale public events security by running “red team” penetration tests, trying to detect the flaws or breaches in the system, and sets about shoring up vulnerable areas.

Broadly speaking, Downing says he has been insisting for years on “creating a culture of first preventers rather than first responders. … It’s up to people who see something out of the ordinary, suspicious activity, to notify law enforcement so that the threat can be addressed.”

A drone hovering over a packed open-air stadium evokes the horror of “Black Sunday,” the 1977 movie thriller in which the Goodyear Blimp plays the leading role in a threat to blow up the Super Bowl. We’ve come a long way since then.

“Drones are a lot cheaper and more accessible,” Downing admitted. “We need to prepare for the worst-case scenario.”