The FBI said Sunday it was investigating “what appears to be an attempted assassination” of Donald Trump at his golf club in West Palm Beach, Florida, just nine weeks after the Republican presidential nominee survived another such attempt.

The plane, a type of experimental aircraft that resembled an extensively modified Piper PA-12, crashed shortly after takeoff Saturday morning, the NTSB’s Alaska chief said.

The decision follows accusations from the city’s former finance administrator that Mayor Tariek Oviok misused public funds, as well as escalating tensions between the mayor and the council over the resulting investigation.