Please answer a question about the following article about Dissolution of the Soviet Union:

On June 16, 1988, 6,000 to 8,000 people gathered in Lviv to hear speakers declare no confidence in the local list of delegates to the 19th Communist Party conference, to begin on June 29. On June 21, a rally in Lviv attracted 50,000 people who had heard about a revised delegate list. Authorities attempted to disperse the rally in front of Druzhba Stadium. On July 7, 10,000 to 20,000 people witnessed the launch of the Democratic Front to Promote Perestroika. On July 17, a group of 10,000 gathered in the village Zarvanytsia for Millennium services celebrated by Ukrainian Greek-Catholic Bishop Pavlo Vasylyk. The militia tried to disperse attendees, but it turned out to be the largest gathering of Ukrainian Catholics since Stalin outlawed the Church in 1946. On August 4, which came to be known as "Bloody Thursday," local authorities violently suppressed a demonstration organized by the Democratic Front to Promote Perestroika. Forty-one people were detained, fined, or sentenced to 15 days of administrative arrest. On September 1, local authorities violently displaced 5,000 students at a public meeting lacking official permission at Ivan Franko State University.

Who led the Millennium celebration in Zarvanytsia?
Pavlo Vasylyk