Passengers on two KLM Royal Dutch Airlines flights from South Africa were stuck on the planes for hours after landing in Amsterdam over concerns of a new COVID-19 variant that has many countries closing their borders again.

The new variant named the “Omicron” variant was first detected in South Africa and has the UK and the Netherlands issuing immediate travel bans. As a result, passengers onboard the two flights were caught in the crossfire.

Both of the 11-hour flights from Cape Town and Johannesburg departed early morning on Nov. 26 and arrived in Amsterdam later that morning, according to FlightAware shows.

While mid-air, travel restrictions over the new COVID-19 variant for South Africa were implemented in the Netherlands at noon Amsterdam time, which ultimately impacted the passengers.

“Passengers of two KL-flights (KL592 and KL598), although landed before noon, [were] not allowed to leave the aircraft after landing, by order of Dutch government and health organizations,” the airline confirmed with Insider.

Travelers were eventually allowed into the terminal but they had to undergo mandatory COVID-19 testing before any were allowed to leave. According to the New York Times, some passengers from Johannesburg had to wait at least four hours before debunking the plane.

As of now, the European Union is discussing the possibility of ceasing flights from southern African countries.

“All air travel to these countries should be suspended,” European Commission President Ursula von der Leyen said. “They should be suspended until we have a clear understanding about the danger posed by this new variant, and travelers returning from this region should respect strict quarantine rules.”

The Netherlands has confirmed 13 cases of the new omicron variant as of Nov. 28 and two cases were found in Australia.

Confirmed or suspected cases of the new variant are also emerging in other European countries, in Israel, and in Hong Kong as reported by CNBC.