audio speaker iconLech Aleksander Kaczyński (help·info) (18 June 1949 - 10 April 2010) was the President of the Republic of Poland from 2005 until his death in a plane crash in Smolensk, Russia on 10 April 2010. Kaczyński served as Mayor of Warsaw from 2002, until the day before he became president. He was a Roman Catholic and was the identical twin brother of the Prime Minister of Poland, Jarosław Kaczyński.