Mexican drug cartels may now reportedly be using weaponised drones with remote detonators. On 20 October, Mexican police pulled over four men in a pickup truck near the city of Salamanca in Guanajuato state and found that the men had an AK-47 rifle, an unmanned aerial vehicle (UAV) outfitted with a "large explosive device" and a remote detonator in their possession.

Although Mexican authorities refrained from clarifying whether the four men had any ties to drug cartels, according to Dr Robert Bunker, a fellow with Small Wars Journal, Guanajuato is at present considered to be a contested area, with several drug gangs, including the Sinaloa cartel, Los Zetas, and Cártel Jalisco Nueva Generación (CJNG) operating in the state.

However, it appears that the use of weaponised drones by drug cartels may not have been too surprising, given how some cartels are known to have previously used drones to smuggle drugs. "This has been expected for some time now," Bunker told Motherboard.

Rival drug cartels have also reportedly used "potato bombs" – hand grenade-sized IEDs – in attacks against each other and against the authorities. According to Bunker, the explosives found by the Mexican police in the pickup truck along with the drone in Guanajuato, are "consistent" with potato bombs. In other words, the drone could likely have been equipped with the explosives to be used in attacks.

"That cartels would weaponise [drones], just like Isis has done, is not surprising," Peter W Singer, author of Wired for War, told Motherboard.

According to some experts, drug cartels could also take a leaf out of Amazon's delivery drones and use UAVs to potentially deliver explosives to their targets. "As both Islamic State and Amazon have shown, small drones are an efficient way of carrying a payload to a target," Nick Waters, an independent drone expert and a former British Army officer said. "Whether that payload is your new book or several hundred grams of explosive is up to the sender."

However, according Waters, there's no need for panic yet, as the drones are more likely to be just a "tool" for the cartels rather than "a game-changing capability". According to Singer, cartels using weaponised drones should cause no more worries as them "using machine guns, car bombs, machetes, etc".

Some cartels are known to have previously used drones to smuggle drugs Bruce Bennett/Getty Images