Two F/A-18 fighter jets crashed off the coast of North Carolina on Thursday, according to the Coast Guard.

Petty Officer Fagal Nifin said four people have been recovered and are being taken to Sentara Norfolk General Hospital. The hospital is the area’s only Level I Trauma Center. Nifin said the extent of injuries is unknown.

Nifin said the crash occurred off the Outer Banks. The area is frequently used for training by fighter jets based at Oceana Naval Air Station in Virginia Beach. The Marines also fly a variant of the jet.

Navy officials did not immediately respond to requests for comment.