PROSECUTORS say a new analysis of evidence from the 2010 plane crash in Russia that killed the Polish president shows that two Russian air traffic controllers and another Russian official in the control tower deliberately contributed to the disaster.

Russian President Vladimir Putin’s spokesman, Dmitry Peskov, quickly rejected the claims.

The crash killed President Lech Kaczynski and 95 others, many of them top Polish state and military leaders. It happened as the Polish crew tried to land in heavy fog at an airport near Smolensk.

A string of claims and counter claims have been made about the cause of the tragedy, including an accusation that Putin was behind it.

Yesterday, deputy prosecutor Marek Pasionek claimed the air traffic controllers were guilty of “deliberately causing an air traffic catastrophe”, and that the third Russian official assisted them.

Polish investigators said they want to question the three Russians and cannot reveal details about the evidence until that happens.

The plane clipped a tree on approaching the runway and crashed into the ground. It was the worst tragedy in modern Polish history and at first united a deeply grieving nation.

But it has since become a highly divisive political issue, pitting liberal Poles against conservative supporters of Kaczynski and his twin brother Jaroslaw Kaczynski, a former prime minister who now heads the populist ruling Law and Justice party.

Jaroslaw Kaczynski has suggested that Putin and the Polish prime minister at the time, Donald Tusk, now president of the EU Council, bear guilt for the tragedy.

Kaczynski and his allies have made a range of allegations, at times suggesting that there was an explosive device on board that brought the plane down or that Putin ordered the assassination of the Polish leader.

Other suggestions have included an unproven claim that the Russians produced fake fog to disorientate the pilots.

They have also alleged that Tusk failed to provide adequate security for the presidential flight and that he failed to properly investigate the tragedy afterwards or get back the wreckage or flight records, which remain in Russia almost seven years later.

Defence minister Antoni Macierewicz sent a note to military prosecutors last month accusing Tusk of diplomatic treason, alleging he worked with Putin to harm Poland’s interests after the crash.

Tusk strongly denies those claims and government critics believe Kaczynski and his nationalistic supporters have been falsely fomenting conspiracy theories to win political points with voters sceptical of both Russia and pro-European liberals such as Tusk.

Some critics said they consider allegations against the Russians as a sign that a commission headed by Macierewicz that is investigating the tragedy has not uncovered anything new.

The commission “should be dissolved because there is no proof of an assassination or a blast”, Newsweek Polska editor Tomasz Lis said on Twitter.

Poland and Rissia carried out separate major investigations into the crash.

The Polish investigation blamed the disaster on a combination of factors, including bad weather and errors made by a pilot who was not adequately trained on the plane he was flying, a Tupolev-154.

That probe also said Russian air traffic controllers gave incorrect and confusing landing instructions to pilots - but it stopped short of alleging intentional wrongdoing.

A Russian investigation at the time put all blame on the Polish side, finding no fault with the Russian air traffic controllers.