Torrential rains in the mountainous area around Rio de Janeiro have triggered one of Brazil's worst ever natural disasters, with more than 800 people dead, according to the latest government figure.
Entire hillsides have collapsed and avalanches of mud and rock devastated largely poor communities, some of which are reachable only by helicopter.
The ACT Alliance of Christian relief agencies said its members in Brazil were supporting the affected population, while churches in the cities have constructed their own emergency responses.
Congregations of the Evangelical Church of the Lutheran Confession in Brazil have established committees to assess needs and plan their relief response alongside other aid organizations and the government.
"This way we want to assist the most urgent requests of those unassisted, and avoid the waste of resources and replication of help," said IELCB synodical pastor Guilherme Lieven. "At the same time, we also need to think both on mid and long term levels, when the media's attention on this region will be gone."
Lieven, who has visited the worst-hit areas, appealed for more cash donations to support those living in temporary shelters.
He told of one Lutheran leader sheltering 18 people in her home.
"It's all very, very sad, but after so much death we have to start thinking and working for life," he said.
Other ACT members – Koinonia, Lutheran Foundation of Diaconia, Ecumenical Coordinator of Services, Diaconia and Christian Aid – all plan to launch appeals for flood relief donations.