AgustaWestland said in a statement that both pilots aboard died in the accident involving a AW609 tiltrotor prototype in the Piedmont region today morning.
The news agency ANSA quoted unidentified witnesses who said the plane exploded before crashing to the grouZnd in the countryside near the city of Vercelli.
The company's website calls the AW609 "a game changer" that combines the vertical takeoff of helicopters with the fixed-wing and rotary-wing flight of airplanes.
AgustaWestland, which is owned by the Italian defense contractor Finmeccanica, says it is cooperating with authorities to determine the cause, and expressed "deepest sympathies" for the pilots' families.