A passenger who complained online about his flight's diversion is being sued by Thai Airways

• A Thai Airways flight to Australia was delayed four hours after it diverted due to poor visibility.
• One passenger questioned the captain's judgment before he hit back on his popular Facebook page.

Thailand's national airline said Thursday it is taking legal action against a passenger who accused it of wrongly diverting his flight.

In a Facebook post, Thai Airways said the passenger had shared "damaging words" after the flight had to land at a different airport due to weather conditions.

Four days earlier, an Airbus A350 flying from Bangkok to Melbourne, Australia diverted to Sydney. It reached its intended destination four hours later than scheduled, per data from Flightradar24.

Aviation news website SimpleFlying reported that a heavy fog obscured the sky and ground visibility was reduced to 200 meters, so it would've been dangerous to attempt a landing.

But one passenger took to Facebook to criticize the captain's judgment. He suggested the weather was fine, questioned the fuel levels, and said the pilot should've been more assertive with air traffic controllers.

One of the airline's pilots, Captain Faisal, runs a popular Facebook page with 200,000 followers. He shared a comprehensive response refuting the accusations.

Thairath, a national newspaper, reported that the passenger deleted his post after facing the captain's lengthy rebuttal.

The passenger also said they planned to apologize to the captain and the airline's management when they were next in Thailand, per the outlet.

In its statement, Thai Airways said it was starting legal procedures because an online post affected public confidence in the company.

The airline didn't immediately respond to a request for comment from Business Insider, sent outside Thai working hours.

Thailand has strict libel and defamation laws that can result in a prison sentence.

Thailand also has a Computer Crimes Act, which makes it a crime to upload "false" information that can "cause damage to the public," per The New York Times.