Ukrainian President Volodymyr Zelensky says Russia is “playing with the lives” of prisoners after 65 died in a plane crash on Wednesday.

The plane, which was also carrying six Russian crew and three escorts, crashed onto the ground and exploded near Belgorod on the Ukraine–Russia border. Russia said there were no survivors.

Moscow had earlier claimed the 65 Ukrainians on board were part of a prisoner exchange. Ukraine‘s military intelligence said it had not been told to ensure a safe flight path for the plane, reports the BBC.

Addressing the nation, Zelenksy said it was “obvious that the Russians are playing with the lives of Ukrainian prisoners, with the feelings of their relatives and with the emotions of our society”.

Zelensky has now called for facts to “be established”. It comes after earlier reports suggested Ukraine had shot down the plane – although it said it had no reliable information suggesting who was onboard.

A video shared on social media showed the Il-76 plane going down followed by an explosion near to the village of Yablonovo, 70km (44 miles) to the north-east of the city of Belgorod. Ukrainian officials initially believed the plane was carrying missiles.

Russia‘s defence ministry said a prisoner swap was due to take place on Wednesday afternoon at a border checkpoint 100km (60 miles) to the west of Belgorod. It said the plane had taken off from Chkalovsky air base north-east of Moscow en route to Belgorod.

It claimed Ukraine‘s air force had fired two anti-aircraft missiles from the Lyptsi area south of the Ukrainian border. Andrei Kartapolov, chairman of Russia‘s parliamentary defence committee, says there can now be “no talk of prisoner exchanges.”

Around 8,000 Ukranians are believed to be held by Russia. Ukraine however says tens of thousands of people remain missing.

The war between Russia and Ukraine is approaching its third year. Air attacks on Ukraine have increased in recent weeks with 18 people killed and 130 injured in missiles strickes on Tuesday.