A drone sprays pesticide in a field in Duchang County of Jiujiang City, east China's Jiangxi Province, July 2, 2015. (Xinhua/Fu Jianbin)

LONDON, May 18 (Xinhua) -- Two men who used drones to fly drugs into prisons in London and Hertfordshire, have been jailed for a total of more than ten years, London's Metropolitan Police said Tuesday.

Tomas Natalevicius, 35, was given seven years and eight months in prison for conspiracy to supply prohibited items into London's Pentonville Prison and conspiracy to supply cocaine and cannabis into a prison in Hertfordshire.

Dalius Zilinskas, 33, was given two years and eight months in prison' imprisonment for conspiracy to supply illegal drugs to the prison in Hertfordshire.

The Met said their police officers were patrolling around Pentonville Prison looking for offenders trying to smuggle illegal items into the prison. They spotted a drone carrying a package towards the prison, but it crash landed, and a car was seen escaping at speed. DNA testing led to Natalevicius being arrested as a suspect.

Police in Hertfordshire spotted another drone flying into The Mount prison, and they arrested Natalevicius and Zilinskas after they were found with a drone control unit.

Prison officers carried out a search of cells at the prison and found drugs and cell phones.

Detective Chief Inspector Steve Heatley from the Met said: "The drones carried a substantial amount of drugs and a large quantity of mobile phones into prisons, which we were able to intercept, thanks to the vigilance of officers and the public.

"The message is clear, if you commit a criminal offence such as this you will be caught and prosecuted," Heatley said.