As Konstantin Kosachyov, the chairman of the Duma's International Affairs Committee, put it: Katyn has claimed yet more Polish victims. Just a few days after the two prime ministers, of Poland and Russia, commemorated the dead of Katyn (and other places) thus acknowledging officially that the Polish officers were murdered by the Soviets not the Nazis, President Kaczynski was killed on his way to the commemoration in the Smolensk forest. He, his wife and other official visitors were on a twenty-year old TU-154 when it crashed. There were no survivors. The Telegraph has an obituary.
UPDATE: AP reports that the total number of dead is 96 and describes scenes of national mourning throughout the country. The Russians seem to be in shock and Prime Minister Putin is taking over the investigation personally, which is not usually a sign that anything very useful will be done. This, however, is a huge international event and not the murder of a Russian journalist or human rights activist. It is also a source of huge embarrassment for Russia with the geographic and temporal symbolism of Katyn ever present in everybody's mind.