Updated

Polish prosecutors allege that a new analysis of evidence about 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.

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 but that no formal accusations have been made yet.

Kuczynski and other investigators made the allegations at a news conference Monday. They 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.