WARSAW, Poland (AP) — Poland's government is accusing European Council President Donald Tusk of betraying national interests and bowing to Moscow in the investigation of the 2010 plane crash in Russia that killed Polish President Lech Kaczynski and 95 others.

Poland's ruling conservative party is led by the late president's twin, Jaroslaw Kaczynski, a political foe who accuses Tusk of contributing to his brother's death. Tusk was Poland's prime minister in 2010.

Defense Minister Antoni Macierewicz, who heads a special commission re-investigating the crash, has notified the military section of the National Prosecutor's Office that he suspects Tusk committed a crime against Poland when he failed to secure Poland's participation in the investigation of the crash near Smolensk, Russia, or the return — to this day — of the wreckage and of the plane's flight recorders.

"Prime Minister Donald Tusk struck an illegal agreement with Vladimir Putin to Poland's detriment and should face criminal responsibility for that," Macierewicz told the Gazeta Polska Daily newspaper.

Government spokesman Rafal Bochenek said Tuesday that Tusk's decision "prevented full investigation of the circumstances" of the crash.

Independent investigations by aviation experts in Poland and in Russia concluded that mistakes by insufficiently-trained crew coupled with poor visibility at the rudimentary military airport led to the crash, which was the worst accident for Poland's state since World War II.

A criminal investigation seeking those responsible is still underway in Poland.

Macierewicz is heading a probe by aviation experts and forensics looking for proof to support his and Kaczynski's views that the crash was an attack on the Polish delegation going to an anniversary memorial for some 22,000 Polish officers and prisoners of war killed by the Soviet Secret Security in 1940 during World War II.