A cargo plane with eight people on board crashed near the city of Kavala in northern Greece late on Saturday, the fire brigade and state TV said.
State TV ERT reported that the aircraft was an Antonov An-12 owned by a Ukrainian company, which was flying from Serbia to Jordan.
The pilot had requested an emergency landing due to an engine problem but the aircraft's signal was lost.
Video footage uploaded on ertnews.gr showed the aircraft in flames descending fast before hitting the ground in what appeared to be an explosion.
The fire brigade could not confirm the type of aircraft but said there were initial reports that eight people were on board.
In a statement it said it had deployed 15 firefighters and seven engines to put out the blaze that broke out after the crash. More rescuers were on their way.
It was not clear what the aircraft's cargo was but the special disaster response unit was also investigating the scene.
"We are treating the cargo as dangerous material," said a fire brigade official.