MOSCOW (AP) — Orthodox Christian believers are observing Easter, a week later than the religious holiday was celebrated this year by Western churches.

In Russia, about 4.3 million people took part in an Orthodox Easter event, the Interior Ministry said Sunday. President Vladimir Putin and Prime Minister Dmitry Medvedev attended Easter services at Christ the Savior Cathedral, Moscow's largest church.

Serbia celebrated the day in a highly charged atmosphere over Kosovo, the former Serbian province whose predominantly ethnic Albanian people declared independence from Serbia a decade ago.

Kosovo is considered by Serbia's nationalists as the cradle of the Balkan state's statehood and religion. Messages from priests during liturgies included political messages.

In Kiev, Ukrainian President Petro Poroshenko attended Orthodox Easter services at the Volodymyrskiy Monastery.