Two police forces have become the first in the UK to launch a fully operational drone unit.
Devon and Cornwall and Dorset police forces began trialling the technology in November 2015 and the unit has now become fully established.
Five officers have been trained, with a further 40 aiming to complete their Civil Aviation Authority (CAA) accreditation in the next 12 months.
There are currently six drones - equipped with a zoom camera and thermal imaging - in operation across the two forces.
The drones take part in missing person searches, crime scene photography and respond to major road traffic collisions.
They also help scour the forces' 600 miles of coastline, as well as woodlands, and help combat wildlife crime.
Some of the drones feature police livery but do not have flashing blue lights or sirens.
Others have been left blank for covert operations.
Chief Superintendent Jim Nye, commander for the Alliance Operations Department, described the unit as an "historic step" for policing in the UK.
"Drone capability is a cutting-edge way to support operational policing across Devon, Cornwall and Dorset," Mr Nye said.
"This technology offers a highly cost-effective approach in supporting our officers on the ground in operational policing."
The unit is currently using DJI Inspire drones, costing approximately £2,000 with the basic camera, and DJI Mavic drones, costing £1,300.
A thermal camera costs about £6,000 and a zoom camera costs £800. Helicopters cost about £800 per hour.
"I think long term, it will be very cost effective to use the drones," Mr Nye said.
"The helicopter isn't always available and you want to have it available for life-threatening situations.
"This is not going to be a replacement to police officers, this is going to complement what we do.
"I think the public would expect that if we can get value for money with a drone over a helicopter, that we do so."
Drones from the trial have been used to help secure convictions in court cases, with evidence from them being used in jury bundles.
They have also located missing people and taken images of major crime scenes, a spokesman for the alliance said.
Mr Nye added that in the future, he anticipated that drones would be used to assist in counter-terrorism operations.
"Drones can even help police track and monitor suspects during a firearm or terrorist incident," he said.
"It will allow officers to gain vital information quickly, safely and allow us to respond effectively at the scene.
"Being the first police forces in the country to have a standalone, fully operational drone unit is a great source of pride for the alliance."
A number of other forces in the UK do use drones, but the alliance is the first such unit.
In the coming months, drones will be used in roads policing vehicles across the unit's area to offer on-the-move technology.
The unit aims to have 40 officers complete their CAA training and become fully accredited by the start of 2018.
Further drones will then be purchased, with the unit obtaining around 12 available by that year.
Footage is gathered using guidance issued by the Information Commissioner's Office.
Andy Hamilton, the drone team manager, said taking aerial photographs or footage had previously been done by the National Police Air Service (NPAS) helicopter.
"Instead of always sending a helicopter on an hour's flight to take a few photos of a crime scene, we can now use a drone," Mr Hamilton, a former police officer, said.
There are 19 helicopters providing air support to police forces throughout England and Wales and the NPAS does not operate drones.
Russ Woolford, NPAS drones lead, said: "NPAS supports the use of drones in policing and is committed to achieving their effective, ethical and safe operation as part of the overall capability for policing from the air."
Drones are limited to a height of 400ft and a distance of 500m away from the operator.
They cannot fly within 50 metres of a person or building without the landowner being informed.
They are also restricted from flying within 150 metres of a congested area, or gatherings of more than 1,000 people.
Police oversee drone use by the public and have issued warnings to five members of the public for breaking rules and regulations.