Surveillance drones are to be deployed by an anti-hunting group to gather evidence of hunts breaking the law.
The League Against Cruel Sports has declared "war" in the countryside and said it will use cameras mounted on the aircraft to monitor any illegal activity that would otherwise be difficult to film on the ground.
The group said evidence from the remote control machines would be collected and passed on to the police.
It claims the move is a "necessary tactic" to crack down on illegal hunting and wildlife crimes such as hare coursing and badger baiting.
The pro-hunting Countryside Alliance, said the deployment raised questions of "civil liberty" and showed the League was becoming "increasingly desperate".
League chief executive Joe Duckworth, said: "There is a war in the countryside and whilst there are still individuals determined to flout the law and seek new ways to avoid detection, the league will continue to explore safe, tested and innovative technology to further our charitable aim of ending cruelty to animals in the name of sport."
It has been illegal to use dogs to hunt animals in England and Wales since 2005.
Hunts are no longer allowed to use dogs to chase foxes, but are instead supposed to use techniques such as drag hunting, where hounds track a trail of a scent laid in advance by a runner or rider dragging a lure.
The League routinely uses clandestine filming to monitor hunts, usually by members concealed in hedgerows and bushes using long lenses and video cameras.
However, the fluid nature of hunting and issues over access to private property can make following horses and hounds over miles of terrain difficult.
The animal rights charity said it would be working with ShadowView, a non-profit aerial surveillance and monitoring organisation.
It said such said drones had already been used by the Ulster Society for the Prevention of Cruelty to Animals in Northern Ireland to deter badger baiters, and by the WWF in operations against poachers in Africa.
Countryside Alliance spokesman Tim Bonner said there were civil liberties questions to answer on drones flying and filming over private property.
"There are some really quite profound arguments going on about whether a non-governmental organisation should be able to carry out these sort of activities without proper scrutiny," he added.
It is legal to fly your own drone in the UK without any special permission if it weighs less than 20kg and is flying more than 150m from a congested area.
A spokeswoman for the League added: "We would only use this equipment if we believed illegal activity was taking place, we wouldn't just go out and monitor anybody."
The Police Federation, which represents rank-and-file officers in England and Wales, said evidence obtained through the use of drones would be treated in a similar way to that obtained using CCTV.
"It would depend on the quality of footage. It would need to be assessed through the relevant procedures," a spokesman said.
