New Delhi (AFP) — Indian officials say at least 68 people are unaccounted for a week after a deadly wall of icy water swept away a Himalayan town and buried it in mud.

On top of four people reported to have been killed, it takes the likely overall toll of the 5 August disaster to more than 70 dead.

Videos broadcast by survivors showed a terrifying surge of muddy water sweeping away multi-storey apartment blocks.

Disaster officials said Tuesday that they were searching for corpses in the wreckage of the tourist town of Dharali in Uttarakhand state.

Gambhir Singh Chauhan, from the National Disaster Response Force, said sniffer dogs had identified several sites indicating there was a body but when “when digging started, water came out from below.”

Chauhan said teams were also using ground penetrating radar in the grim search.

More than 100 people were initially reported as missing.

But with roads swept away and mobile phone communications damaged, it has taken rescuers days to cross-check the list.