South Africa's President Jacob Zuma said on Tuesday that 67 South Africans died in the Synagogue building collapse that happened last Friday in Lagos.
Investigators believe the strain of additional stories under construction on top of the house caused the collapse.
"I am greatly saddened to announce that 67 South Africans died and scores of others sustained injuries, after a building at the Synagogue Church of All Nations collapsed on Friday," Zuma said
His statement indicates that the total number of casualties may be far higher than previously thought.
Declaring a nation in grief, Zuma said, "This is a particularly difficult time for South Africa. Not in the recent history of our country have we had this large number of our people die in one incident outside the country. Our thoughts are with the families, friends and colleagues that have lost their loved ones in this heartbreaking tragedy. The whole nation shares the pain of the mothers, fathers, daughters and sons who have lost their loved ones. We are all in grief."
Nelson Kgwete, a spokesman for South Africa's Department of International Relations and Cooperation, said at least five South African church tour groups were at the complex at the time of the collapse. He said officials from the South African Mission in Lagos were liaising with rescue workers at the scene to assess the situation. The South Africans were in Nigeria to seek spiritual help and were staying at the guesthouse before it collapsed.
Zuma said he had ordered government departments to help family members get to Nigeria to identify the bodies of their loved ones, and repatriate the remains as soon as possible. Zuma also extended his condolences to the people of Nigeria and "all other nations affected by this tragedy,"
It is unclear if there are any more victims or what their nationalities would be as spokesperson for Nigeria's National Emergency Management Agency (NEMA) is yet to respond to a request to clarify the casualty figures.