Tens of thousands of people in Ukraine on Friday took part in events marking the 1,030th anniversary of the Christianisation of the country, marching through Kiev in a religious procession backed by arch enemy Moscow. Clergymen, several pro-Russian opposition lawmakers and ordinary people who took part in the procession through central Kiev amid a heavy police presence were supporters of the Ukrainian Orthodox Church backed by Moscow.
According to police, 20,000 people took part in the event, while organisers put the turnout at 250,000 people.
Some 5,000 police were deployed to ensure order amid fears of possible clashes with Ukrainian nationalists.
On Saturday, President Petro Poroshenko is expected to take part in a rival religious procession backed by the breakaway Ukrainian Orthodox Church.
Kiev was the capital of the ancient pagan Slavic state of Kievan Rus which was converted to Christianity by Prince Vladimir in 988.
The Ukrainian Orthodox Church declared autonomy from Moscow's religious leadership after the country gained independence from former master Russia in 1991.
The outbreak of the separatist conflict between Kiev and Kremlin-backed rebels in the east of the country in 2014 has exacerbated those tensions, with Patriarch Filaret of the Kiev-based Ukrainian Orthodox Church famously saying Russian President Vladimir Putin was "possessed by Satan."