A United Airlines flight was traveling from Lagos to Washington, D.C. when it experienced "sudden aircraft movement."

A United Airlines flight from Africa to Washington D.C. had to turn around on Thursday after a "technical issue" caused "unexpected aircraft movement," the airline said.

United Airlines said it was cooperating with U.S. and Nigerian investigators to determine what exactly happened on the flight.

Six people were taken to hospital with injuries but have been discharged, United Airlines said.

It is unclear what caused the jolt; United Airlines has said the cause was not severe turbulence, and that it is “working with aviation authorities in the US and Nigeria to understand the cause.”

The plane headed back to Nigeria after experiencing "unexpected movement" mid-flight on Friday, Jan. 24, according to multiple reports

Six people were injured on a flight from Nigeria to Virginia. The airline also saw a series technical issues in March.

Nearly 40 people were injured, with six seriously injured, when a Boeing aircraft operated by United Airlines suddenly plunged in mid-air, forcing the fight to make an emergency landing.

The Nigerian Airspace Management Agency (NAMA) has explained why United Airlines chose to make air return to Nigeria during its

The same United Airlines aircraft had a similar issue earlier this week, with a rapid altitude drop prompting a diversion.

Six people were taken to hospital, and many more were injured after a United Airlines flight from Lagos heading to Washington D.C. experienced a sudden in-flight movement. The United States has opened a probe into the unexpected movement, as the cause is still unknown.