Dutch police are to begin using drones to help solve crimes and monitor crowd behaviour this year.

‘The question is not if we are going to use drones but when,’ spokesman Casper Steenstra-Praamsma told broadcaster Nos at the weekend.

Drones – small, unmanned aircraft – can be used to observe hostage situations, record crime scenes and observe crowds and demonstrations without the use of expensive police helicopters, Steenstra-Praamsma said.

The first 15 police drone pilots are expected to complete their training in the next few months.

Privacy

Privacy expert and lawyer Martin Hemmer told Nos that the police will have to have a specific reason to send out a drone, such as to track a suspect or in response to a threat to public order.

They will also have to make it clear to event organisers if drones are being used to monitor visitors, he said.

‘Their use must be proportional,’ he said. ‘The interests of people who are not being investigated must also be taken into account. They must also make sure that the use of drones has as little impact on ordinary people as possible.’

Hobby

New rules governing the use of drones came into effect at the end of 2015. A mini drone is not allowed to fly higher than 50 metres or 100 metres from the controller.

Drones will also have to keep a distance of 50 metres from people, buildings and other unmanned aircraft. Nor can drones be flown within five kilometres of airports.

The Dutch association of professional drone users estimates there are some 100,000 of the unmanned flying machines in the Netherlands.