Estonia and Sweden are paying tribute to the 852 people killed two decades ago when a passenger ferry sank in a storm on the Baltic Sea.

Hundreds of Estonians gathered Sunday to place flowers at the monument honoring the victims of M/S Estonia in central Tallinn after attending a memorial church concert late Saturday.

Various memorial events were also held in Stockholm on Sunday.

The ferry sank in heavy seas while on a voyage from Tallinn to Stockholm early on Sept. 28, 1994.