Twelve people were injured after a Qatar Airways flight from Doha to Dublin was hit with turbulence on Sunday.

The flight, which landed in Dublin shortly before 1pm local time, was met by emergency services, including airport police and the fire and rescue department.

According to a statement from Dublin Airport, six passengers and six crew members were injured in the incident, eight of which were taken to hospital following assessment. The Qatar Airways flight QR107 experienced turbulence while flying over Turkey, the statement said.

Dublin Airport said it was assisting passengers and staff and that operations were unaffected. The plane’s return flight to Doha, flight QR018, is scheduled to go ahead as expected, though its departure will be delayed, the airport said.

“The matter is now subject to an internal investigation,” the statement continued. “The safety and security of our passengers and crew are our top priority.”

It comes days after 104 passengers were injured and a man with a heart condition was killed on a Singapore Airlines flight that was hit with severe turbulence.

Flight SQ321 from London to Singapore was cruising at 37,000 feet on Tuesday when the plane dropped sharply before climbing several hundred feet, according to flight tracking data. It then repeatedly dipped and ascended for about a minute.

Is turbulence on the rise?

About 65,000 aircraft suffer moderate turbulence every year in the US, and about 5,500 run into severe turbulence. These numbers, however, might be destined to grow.

“We ran some computer simulations and found that severe turbulence could double or triple in the coming decades,” Williams said.

The findings, which were later confirmed by observations, highlight a type of turbulence called “clear air turbulence,” which isn’t connected to any visual clues such as storms or clouds. Unlike regular turbulence, it hits suddenly and is hard to avoid.

It is not yet known what kind of turbulence the Qatar Airways plane experienced.

CORRECTION: This article has been updated to reflect that the cause of the turbulence that hit the Singapore Airlines is yet to be determined and that investigations are ongoing.