The military has deployed 1,050 of its personal in rescue efforts, said its spokesman Brig. Roshan Seneviratne.
An estimated 70 to 100 houses have been destroyed in the incident two days ago.
People of the area accuse politicians of having committed murders, as they had not listened to their repeated calls to remove the waste dump.
The present regime and its predecessor are responsible for these loss of lives, said Nuwan Bopage, organizer of the people’s movement against the waste dump.
He has told BBC Sinhala that the bodies of the nearly 20 missing would not be recovered, as they were buried under 40-feet of earth.
Sections of the government are accusing each other over the incident, while area residents as well as officials level the finger at the previous Rajapaksa regime too.
In a statement, prime minister Ranil Wickremesinghe said the government was sorry the tragedy struck before its plan to remove the waste dump could be implemented.
The government has now announced that no more waste would be dumped at Meethotamulla, and that waste would be dumped at two other locations.
People have banned politicians from attending the funerals today (16) of 12 people who died in the waste dump collapse.