Polish prosecutors alleged Monday that a new analysis of evidence into the 2010 plane crash in Russia that killed the Polish president shows that two Russian air traffic controllers and a third person in the control tower willingly contributed to the disaster.
The Russian government strongly denied the allegations.
Poland's National Prosecutor Marek Kuczynski said there is "no doubt" that one of the causes of the crash was the behavior of those in the control tower. He said they were guilty of "deliberately causing a catastrophe."
Polish investigators said they want to question the three Russians and cannot reveal details about the evidence until they have spoken to them.
The crash on April 10, 2010, killed President Lech Kaczynski and 95 others, many of them top Polish state and military leaders.
Dmitry Peskov, spokesman for Russian President Vladimir Putin, rejected the Polish claims.
"The circumstances of this tragedy have been thoroughly studied, and we cannot agree with such conclusions," Peskov said.
There were two major investigations into the crash separately carried out by Poland and Russia.
The Polish investigation blamed the disaster on the errors and poor training of the Polish pilots who tried to land in foggy conditions. The Poles also said that Russian air traffic controllers gave incorrect and confusing landing instructions to pilots. But that report stopped short of accusing the Russians of intentional wrongdoing.
A Russian investigation at the time put all blame on the Polish side, finding no fault with the Russian air traffic controllers.
Poland opened a new investigation into the disaster after the election in 2015 of the conservative party Law and Justice, headed by the late president's twin brother, Jaroslaw Kaczynski.
For years Kaczynski and some of his supporters have suggested that Russia intentionally killed Lech Kacyznski and the 95 others, among them the first lady, generals, the head of the central bank and other top officials.
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