British investigators now say the collision never happened, contradicting the plane’s pilot, who had said the plane hit a drone while landing at the London’s Heathrow Airport on April 18. The incident didn’t cause any damage to the plane, and none of the passengers on board were injured.

The United Kingdom’s transport secretary Patrick McLoughlin said on Thursday that the mishap “was not a drone incident,” according to a BBC report. McLoughlin’s comments follow an investigation into the incident by the Air Accidents Investigation Branch, which investigates airplane accidents in the United Kingdom. That group said that it closed its investigation into the incident due to a lack of evidence, according to a report on Thursday by The Guardian.

Last week, in prelude to the official findings, Robert Goodwill, the United Kingdom’s minister of state for transport, told government members that the pilot may have misidentified the object that hit the plane. “There is indeed some speculation it may have been even a plastic bag or something,” Goodwill said, according to The Guardian.

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“The pilot has a lot of other things to concentrate on [when landing] so we’re not quite sure what they saw,” said Goodwill, according to the report.

The investigation’s findings about the Heathrow Airport incident comes a month after a pilot in France claimed to have seen a drone fly close to his airliner while approaching for landing in Paris.

In March, the Federal Aviation Administration released a report that said nearly 600 drones flew dangerously close to both airplanes and airports during a period of time between Aug. 22, 2015 through Jan. 31, 2016. The frequency of such close calls is believed to be rising as drones increase in popularity.

Still, the Academy of Model Aeronatics, an aviation advocacy group that helped the FAA create a national drone registration system, downplayed some of the ominous warnings of danger. It examined the FAA’s latest drone sighting report and claimed that not all of these hundreds of sightings constituted a “close call.”

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The group’s authors said that many of the incidents were merely just someone claiming to have seen a drone in flight, which is far short of being at risk of causing an accident.

“The FAA needs to better analyze and categorize pilot reports to indicate which present serious safety risks (near mid-air collisions) and which could be more appropriately classified as sightings,” the report said.