(CNN) -- Federal authorities are investigating the crash of small plane in northern Michigan town of Saint Ignace that killed four people and injured a fifth.
"The plane encountered some form of difficulty after becoming airborne, the plane crossed over northbound I-75 and struck the median barrier, flipped over and crashed coming to rest on the shoulder of southbound I-75," the Mackinac County Sheriff's Office said in a statement.
A 13-year-old boy, who was ejected from the twin-engine Beachcraft 58, was the lone survivor. He was airlifted to a hospital, the statement said.
The sheriff's department said everyone on board the plane was related.