KLM has issued this statement:
Martinair has been informed that a Convair aircraft has crashed in South Africa. The aircraft was painted in Martin’s Air Charter (retro) livery, but is not operated nor owned by Martinair.
The Convair aircraft was destined for the Dutch aircraft museum Aviodrome at Lelystad Airport in The Netherlands, which is also the owner of the aircraft.
Martinair wishes to send it’s sympathy to the passengers and crew and all others involved in this accident.