It might not have been a drone that struck a British Airways plane on April 17 after all.

British Transport Secretary Patrick McLoughlin told Parliament on Thursday that it was probably "not a drone incident," according to The Register, an online tech publication.

The plane landed safely at London's Heathrow Airport, but reports that it might have been hit by a drone prompted calls for stronger regulation, as The Two-Way reported.

U.K. aviation officials looking into what happened to the Airbus A320 have now ended their inquiry, according to The Guardian. It adds:

"An investigation launched by the Air Accidents Investigation Branch (AAIB) has been closed due to lack of evidence. A spokesman for the AAIB said: 'We made initial inquiries but there was insufficient information on what object was involved for us to take it further.' "

"They just don't have any evidence to tell them one way or the other," BBC's transportation correspondent reports.

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