A drone was flown towards a light aircraft in a bid to cause a mid-air collision, a pilot has claimed.
The near-miss happen as the PA31 aircraft was coming in to land at RAF Northolt, west London, on 11 June.
The gadget was flown just 20 feet below the plane.
A report by the UK Airprox Board (UKAB), based on the recollection of the PA31 pilot, stated: "He lost sight of it under the nose and looked down at the wing root and identified it as a small white drone of the lightweight hobbyist type, it was about 20 feet below the aircraft as he passed over it.
"He reported that he had no doubt that it was being deliberately flown under the flight path in an attempt to collide with an aircraft."
The document went on: "He reported that the drone had passed close to his right wing and that it was possibly launched from a park."
The UKAB classified the incident as having the most serious degree of risk.
Research part-funded by the Department for Transport (DfT) found that a drone weighing 400 grams could smash a helicopter windscreen, and one weighing 2kg could critically damage an airliner's windscreen.
The number of near-misses between drones and aircraft has risen from six events in 2014 to 93 last year.
The DfT is considering banning children from owning drones weighing at least 250 grams as part of a safety crackdown.
Children would only be able to fly the heavier devices if they were owned and registered by an adult.
Other measures included in a consultation launched last month include giving police the power to issue on-the-spot fines of up to £300 for misuse and the ability to seize drones being used irresponsibly.
The DfT is also considering using new technology to protect public events, critical national infrastructure and prisons from drone disruption.
Drones are banned from flying above 400 feet, and within one kilometre (0.6 miles) of airport boundaries.
Anyone breaching these restrictions faces penalties of up to £2,500 and could also be charged with recklessly or negligently acting in a manner likely to endanger an aircraft or any person in an aircraft, which has a maximum sentence of five years in prison.
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