Eleven airline passengers and crew were hospitalized Tuesday following severe turbulence on a Delta flight from Milan to Atlanta, the US-based airline said.

“Delta Care Team members are mobilizing to connect with customers on Delta Flight 175 that experienced severe turbulence before landing safely in Atlanta Tuesday,” a spokesman said.

“Our priority is taking care of our customers and crew who sustained injuries.”

It is unclear how many total people out of the 151 passengers and 14-member crew were injured beyond the 11 taken to hospital, or what the extent of the injuries are for those hospitalized.

Major Hurricane Idalia is currently whipping up fierce winds off the US Gulf Coast and forecast to make landfall in Florida early Wednesday, and another storm, Hurricane Franklin, is swirling in the Atlantic. But neither Delta nor the US aviation regulator attributed Tuesday’s turbulence to the hurricanes.

The Federal Aviation Administration, which reported that the turbulence occurred some 40 miles (64 kilometers) from the Atlanta airport, will investigate the incident, a spokesman told AFP.

Scientists have reported that so-called “clear-air turbulence” — which is hard to predict and happens without obviously bad weather, typically occurring above 15,000 feet — is becoming more frequent due to climate change.