A cargo plane which crashed in northern Greece was carrying 11 tonnes of weapons - including land mines - to Bangladesh, officials say.
People living within two kilometres of the site where the Antonov-12 came down have been warned to stay indoors.
The aircraft was flying from Serbia to Jordan when it crashed late on Saturday close to the city of Kavala, killing all eight people on board.
Eyewitness video showed the plane on fire and a huge fireball as it crashed.
On Sunday morning, drones were being used to survey the site of the wreckage out of caution.
State-run TV reported the army, explosives experts and Greek Atomic Energy Commission staff would not approach the site until it was deemed safe.
"The (air) measurements at the moment have not shown anything but nonetheless instability in the field was observed," Lieutenant General Marios Apostolidis, of the Northern Greece Fire Brigade, told reporters.
"In other words, intense smoke and heat, as well as a white substance that we do not recognise, so a special armed forces team has to inform us what it is and whether we can enter the field."
The pilot had reportedly requested an emergency landing at Kavala airport due to an engine problem shortly after take off, but was unable to reach the runway.
The plane was noticed at about 22:45 local time (19:45 GMT) by local residents.
Aimilia Tsaptanova - who saw the plane come down - said she was amazed it hadn't crashed into their homes.
"It was full of smoke, it had a noise I can't describe and it went over the mountain," she said. "It passed the mountain and turned and crashed into the fields.
"There were flames, we were scared. A lot of cars came, but they couldn't approach because there were continuous explosions."
Serbia's Defence Minister Nebojša Stefanovic said that the Antonov AN-12 was transporting almost 11 tonnes of Serbian-made weapons to Bangladesh.
It was due to make stops in Jordan, Saudi Arabia and India before reaching its final destination of Dhaka.
The plane was being operated by Meridian, a Ukrainian cargo airline, although so far, there is no indication of any connection with the war in Ukraine.
BBC
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