The ceremony for the largest Unification Church mass wedding in a decade has begun in South Korea.

The "blessing ceremony" for more than 21,000 people is taking place at the university campus the Rev. Sun Myung Moon founded in Asan, south of Seoul. An additional 20,000 are marrying or renewing vows at dozens of ceremonies held simultaneously worldwide, from Sweden to Brazil.

There was no sign yet Wednesday of Moon, who is to offer blessings and issue the vows later in the ceremony.

It's the church's largest mass wedding in a decade and comes as the controversial, 89-year-old religious leader moves to turn over day-to-day control of the church to his sons.