Londoners are among Britons missing after flash floods in Nepal that have killed at least 469 people.

More than 30 British nationals are among hundreds of people missing and feared dead as rescue efforts continue following flooding in the Rasuwa district, which borders China’s autonomous region of Tibet.

Rescuers are scrambling to search for survivors after a suspected glacial collapse on Wednesday caused rivers to burst their banks and covered populated areas in thick mud and burying houses.

Videos posted on social media appeared to show huge floodwaters surging through valleys as people screamed in terror, with bridges being washed away.

A number of Londoners are missing following the tragedy.

Hema Amin, 63, from Croydon, south London, was visiting the region to trek on a pilgrimage from Nepal to Tibet with operator Alpine Eco Trek when the wave hit.

Her husband, Sunil Amin, told Sky News of his ordeal in trying to get in contact with his missing wife, saying: “I keep trying to call her. I’ve been trying, trying, trying.”

Nabhi Nandan Das, a Hindu priest from south London, was leading a group on a tour to Mount Kailash and Lake Mansarovar.

The Telegraph reported that the 64-year-old priest, who lives in Streatham, works at the Sanatan Mandir and Community Centre in Coulsdon, Surrey, and was leading 11 Britons, including a missing 13-year-old girl, on the tour.

Other missing Britons include Sarada Simkhada, a senior nurse at Darent Valley Hospital in Kent, who was in Nepal making a pilgrimage to Mount Kailash.

Her brother Shambhu wrote on social media: “My dear sister, wherever you are, please stay strong. We are praying for your safety every moment and waiting desperately for you to return home.”

Leena Bector, a director of a care agency from Slough, Berkshire, who is among 27 travellers associated with the Fishtail Tours and Travels group currently unaccounted for.

Her husband, Bhupesh Bector, told The Times: “I know that she’s in Nepal for sure… so even if they find her today or tomorrow, I need to be there.”

Nepalese tour operator The Trekkers’ Society said nine British nationals on one of its tours to the site were among those unaccounted for – four males, aged 14, 50, 50, and 54, and five females, aged 40, 46, 50, 50, and 53.

Mala and Bipin Patel, from Coventry, went missing after travelling to Nepal and Tibet on a pilgrimage.

Their son, Anant Patel, told Sky News he was “shocked” at the lack of information about their whereabouts.

Mr Patel said: “I think from our perspective, we’re not just shocked that our parents appear to be missing, but also… the ongoing lack of certainty is causing further distress.”

Sumitra Poudel disappeared in the floods and her 24-year-old British businessman husband flew to Nepal on Thursday to search for her as well as his mother, uncle and brother.

Pramod Poudel, who runs a Nepalese street food company in Sussex, told The Telegraph: “The flood came and took everyone, including the house.

“I haven’t heard from them because there’s no power or anything. I am very sad.”

In an update on Friday morning, Nepal’s National Disaster Risk Reduction and Management Authority (NDRRMA) said 469 bodies had been recovered, 977 people remained unaccounted for and more than 3,000 had been rescued following the disaster.

On Thursday, the authority said 517 foreign nationals were out of contact.

Officials have warned of a possible further flooding risk from a lake of rising water at the flood site along the China-Nepal border.

China has warned that a barrier lake formed at the confluence of the Tsogyal and Purupqiangzangbu rivers is overflowing and could burst.

NDRRMA said satellite information from China suggested the river was “blocked” and a lake had formed near the site of the floods.

China’s Ministry of Water Resources said the lake and was expected to receive another three million cubic metres over the next three days.

The Nepal Army said it had sent a team to the border to inspect the Bhotekoshi River.

The UK has offered £5 million to help the Nepalese government amid a “very distressing and devastating situation”, the Prime Minister said.

The King said he and the Queen were “heartbroken” and sent their “most profound sympathy” to those affected.

Foreign Secretary Ed Miliband said on Thursday evening that the FCDO’s crisis centre was working “around the clock” to help Britons affected by the floods.

In a post on social media Mr Miliband said: “We’ve offered an initial £5 million to help with the response to the effort in .

“And indeed we’ve also made an offer in my conversation with the foreign minister from this morning of search and rescue and other help should the Nepalese need it.”