Polish President Lech Kaczynski, his wife, and almost 100 others were killed Saturday morning when their plane crashed in western Russia. The group, which included government officials, relatives of Polish prisoners of war, and clergy, including Catholic Bishop Tadeusz Ploski, were traveling to commemorate the 70th anniversary of the Katyn Forest massacre, where Soviet Secret Police killed 20,000 Poles.

President Kaczynski, a Catholic, was a champion of Christian values and advocate for continuing the country’s Catholic legacy, along with his twin brother, Law and Justice Party leader and former prime minister Jaroslaw Kaczynski.

Pope Benedict XVI offered his condolences to the people of his predecessor’s homeland:

“I entrust all the victims [...] to the goodness of the merciful God,” he said. “In expressing my deepest condolences, from my heart I assure intercessory prayers for the victims and prayers of support for the beloved Polish nation.”

Chicago, the city with the largest Polish population outside of Warsaw, was particularly affected by the tragedy. Chicago artist Wojciech Seweryn, who sculpted a memorial dedicated to the Katyn victims, was among those killed.

“He was so dedicated to remembering this tragedy that happened in 1940,” Father Michael Osuch, Seweryn’s pastor at St. Hyacinth Basilica on the Northwest Side, said. St. Hyacinth’s held a special Mass to pray for the victims. Other churches did as well.