On January 1, at the inauguration of Brazilian president Luiz Inácio Lula da Silva, police detected four unidentified drones converging on the new head of state.
Unmanned aerial vehicles had been used in an assassination attempt on a South American leader before, but this time the security forces were prepared.
Moments later, presidential bodyguards used a relatively new kind of drone gun to jam and "take down" the four suspicious aircraft, according to reports.
Images from the event showed men in dark suits with enormous, unusually designed rifles.
As it turns out, they were drone guns made by a Sydney-based company that has recently scored a series of big contracts with government agencies.
Founded eight years ago after a modest crowdfunding campaign, DroneShield is now riding a wave of demand for drone counter-measures. Its success is partly the result of high-profile incidents such as the one in Brazil, as well as the unprecedented use of drones in the war in Ukraine.
So how did an Australian company find itself selling cutting-edge drone technology to the world?
Betting on the dark side of drone applications
The story of DroneShield is about the thousands of different and often unexpected uses that have been found for drones within a short space of time.
In just eight years, small and cheap "quadcopter" drones have gone from playthings to tools of war, espionage, smuggling and terrorism.
"Drones at the beginning were literally a toy for kids, and now they're being used in war," said Brian Hearing, who co-founded DroneShield in 2014.
Back then, he and DroneShield co-founder John Franklin thought the main customers for drone counter-measures would be hotels and celebrities worried about paparazzi.
"There were anecdotal reports of drones being flown over your neighbour's pool — we thought privacy issues were going to be the main driver."
Initially, Dr Hearing, a scientist, partnered with Dr Franklin, a physicist, to crowdfund "about $US50,000" to develop a system for acoustically detecting drones.
Two years later, the company released its first drone gun — a cumbersome 15kg weapon resembling something from the movie GhostBusters.
Then in 2018, an event occurred that made it abundantly clear there was more to drone counter-measures than swatting away persistent paparazzi.
Shortly before Christmas, a string of unconfirmed drone sightings over two days closed the runways of Gatwick airport near London, grounding hundreds of flights.
DroneShield saw a spike in sales as terrified airport managers stocked up on counter-measures.
Oleg Vornik, who joined the company in 2015 as its third employee and is now CEO, said he had seen the potential of DroneShield from the start.
"We had this vision when we started that drone technology, along with all of the positive applications, was going to have a nefarious or dark side to it," he said.
The following years saw this vision of drone-enabled violence come to pass.
In 2019, Houthi rebels started using drones to damage and destroy oil-generating assets in Saudi Arabia.
"The Middle East were our biggest customers," Mr Vornick said.
Then prison operators were on the phone. Drones were being used to drop drugs, mobile phones and other contraband in prison yards.
A US inmate even broke out out of a maximum-security prison using wire cutters apparently flown in by drone.
"Prisons were writing to us, saying 'We are seeing a ton of contraband deliveries. Please help us,'" Mr Vornick said.
Drug cartels, meanwhile, were also experimenting with the aerial delivery vehicles to evade US-Mexico border security.
The drone war in Ukraine
But by far the biggest impact on the company's reputation came in February 2022: Russia invaded Ukraine and started a conflict that has become a testing ground for new kinds of warfare.
That first month, according to Mr Vornick, Ukrainians were already using DroneShield drone guns.
"We started getting involved through a European military aid contract right at the start of the war," he said.
Both sides were using drones in ways rarely seen before, including to direct artillery strikes, drop grenades behind enemy lines, and as kamikaze missiles.
Russia has used waves of explosive drones to knock out power in Ukraine, damage buildings and facilities, and terrorise people.
"People are starting to realise that nefarious uses for drones are very real."
Last month, DroneShield announced an $11 million purchase order by an unnamed government agency.
The deal surpassed its entire revenue for 2021.
Three weeks later, it announced a second $11 million order, also by an unnamed government agency.
David Dunn, a professor of international politics at the University of Birmingham, said DroneShield was the current "shining star" of drone counter-measures.
"I've seen the equipment being used in Ukraine," said Professor Dunn, who was one of the first to identity the military uses of commercial drones.
"DroneShield has a particular utility in the situation in Ukraine where the explosion in the use of drones has made a huge difference to the war."
In October last year, the US Department of Defence recommended that DroneShield become part of its solution to counter unmanned aircraft systems.
It was a big win for the company — inching it closer to enormous US defence procurements.
"For the Americans, it's as much counter-narcotics and counter crime as it is anything else," Professor Dunn said.
How a drone gun works
Stopping a small and fast-moving drone is remarkably hard. Methods range from capture nets and lasers to projectiles and jamming systems.
DroneShield's guns use the jamming method.
The device sends a burst of radio frequency signal that overwhelms the drone, so that it lands itself or returns to its controller, said DroneShield's Oleg Vornick.
"The best analogy is to say that you and I are talking, and somebody comes up next to us with a loudspeaker and shouts over the top of us," he said.
"You're the pilot, I'm the drone, and the loudspeaker is the jammer."
France, meanwhile, is experimenting with a powerful anti-drone laser cannon it expects to use during the 2023 Rugby World Cup and the 2024 Paris Olympics.
UK airports have been using a system that fires 12-gauge shotgun rounds each packed with a net, which opens after a specific time to ensnare the drone.
For a time, the Dutch were training birds of prey to attack drones, and equipping them with booties made from the material used in bulletproof vests.
"[The birds] would actually take a few of these things out, but then think, I'm going to get hurt doing this, I'm not going to do it again," Professor Dunn said.
Despite all these varied efforts, he added, for the past decade "the offensive has dominated".
Given this history, DroneShield's recent successes may prove to be fleeting.
"The drones being taken down by DroneShield will be retrofitted with interfering technologies," he said.
"[DroneShield] is the technology of the moment, whether it will be in two or five years time is another matter."
Deployed at Australian airports
DroneShield has won over $6 million in contracts with the Australian Department of Defence since 2019, according to the AusTenders website.
"We are supplying defence … and also law enforcement," Mr Vornick said.
DroneShield counter-measures have also been deployed at at least one Australian airport.
"I can't confirm which one it is, but it's a major tier-one airport," Mr Vornick said.
In December 2021, DroneShield won an exemption to the Australian Communications and Media Authority's ban on the use of jamming devices.
Airservices Australia, the Department of Defence and the Civil Aviation Safety Authority (CASA) have collectively deployed drone detection technology (i.e. passive not active drone counter-measures) at 29 Australian airports, according to a 2020 federal government report.
CASA partnered with Airservices in 2019 to detect and track drones near major airports, a spokesperson confirmed.
"We use this information to identify areas for our airport safety educational campaigns."
A spokesperson for AirServices Australia added that it's trialling "the latest-generation detection capabilities that combine radiofrequency, radar, and optical solutions" at Sydney Airport.
The war comes home
Both co-founders of DroneShield, Brian Hearing and John Franklin, left the company in 2017 and 2020 respectively, but remain shareholders.
"With the recent large military contract awards, it's apparent that DroneShield has matured into a government defence contractor," said Mr Franklin, who's based in Washington DC.
"I hope to see the company transform from a small Australian defence contractor into a big international defence contractor."
With the lessons learned from Ukraine, Professor Dunn expects civilian drone defences to be beefed up right around the world.
"There are very easy means to take the innovations on the battlefield in Ukraine and apply those to terrorist settings," he said.
Airports, stadiums, other venues for large public assembly, critical infrastructure, and even commercial shipping are all vulnerable to drone attacks.
"The market is absolutely enormous."
DroneShield stands to profit from this demand, but the future isn't all rosy.
Other, much larger defence contractors are working on their own methods of taking down drones. Then there's the problem of DroneShield's counter-measure technology getting countered itself.
"A lot of these technologies that have been developed in the past five to ten years have been the bright shining star in the market for a period, then the technology that they're trying to counter has found a way of overcoming them," Professor Dunn said.
"People say, 'You put a man on the Moon, you should be able to stop a drone.'
"And the counter-argument is, 'Yes, but the Moon wasn't fighting back.'"
