More than 67 South African’s who were among 300 Christians on a visit to Nigeria, have been reported killed after a church guesthouse they were staying in collapsed last week. An unknown number of people are still unaccounted for.

President Jacob Zuma said at least 67 South Africans died in Friday’s accident at the Synagogue Church of All Nations in Lagos and described it as one of the worst tragedies in South Africa’s recent history, Reuters reported, adding that the collapse occurred when three extra stories were being added to the existing two of a guest house on the church compound.

The Pentacostal church, led by the charismatic “Prophet” T.B. Joshua, attracts a global following of Christians who believe Joshua is able to perform miracles including curing the ill and raising the dead from the grave.