President Koroma fought back tears as he toured Regent on Tuesday and said the devastation was "overwhelming us". Thousands of people lost their homes.
United Nations spokesman Stephane Dujarric said in NY the United Nations country team was "supporting national authorities in rescue operations, helping evacuate residents, providing medical assistance to the injured, registering survivors, and providing food rations, water and dignity kits to those affected".
Authorities requested air conditioning units to keep the bodies cool but are in need of more protective gear such as masks, aprons, and glove disposal stations, said Idalia Amaya, an emergency relief co-ordinator for Catholic Relief Services.
Some 200 people are still missing from the mudslide, the agency said. According to Sky News, ActionAid's director said there are over 1,500 people reported missing.
Officials expect corpses to pop up in unexpected places for months to come, as many bodies were carried away from the Regent area by floodwaters.
A statement from the West African body stated that the President of the Economic Commission of West African States is already in Sierra Leone, meeting authorities over the disaster. "As we are still in rainy season, more flooding is still possible", said Adele Fox, coordinator of health for the NGO Concern Worldwide.
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Their hope was that the meeting would not quorate and thus be unable to proceed and take binding decisions. Khoza said she didn't want to comment on the letter, as it was not delivered to her.
The mudslide happened after part of Sugar Loaf mountain collapsed. Many victims were asleep in bed when disaster struck.
Buhari, who expressed her heartfelt condolences to Mrs Koroma, and Sierra Leone people prayed to Almighty God to give the families the fortitude to bear the loss.
"Most of the people I spoke with today are the sole surviving members of their family", Kallon said. Witnesses described a particularly hard-hit area in the Regent district, saying roads became "churning rivers of mud". "The entire AU family stands united with the people and government of Sierra Leone during this hard time". One witness spoke to the BBC and said that the mud was too fast.
"Deeply saddened by the devastating consequences of the mudslide on the outskirts of Freetown, His Holiness Pope Francis assures those who have lost loved ones of his closeness at this hard time", read an August 16 telegram signed by Vatican Secretary of State Cardinal Pietro Parolin read.
Other residents were up at the time because of the heavy rains. There were hundreds of them, and I lost count of the number.