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170 people - 148 employed at the NTPC plant and 22 at Rishiganga - are still missing. Twelve people trapped in an under-construction tunnel have been rescued by an ITBP team. Around thirty others are trapped in a second tunnel, reportedly around 2.5 km long, and rescue teams worked through the night to save them.
14 bodies had been found so far. Uttarakhand Chief Minister Trivendra Singh Rawat who visited Chamoli district on Sunday, said rescue teams were "doing their best to save the lives of the workers". He also said a team of scientific experts would work to establish the exact cause of the disaster at a later stage.
Mr Rawat also announced Rs 4 lakh compensation for the family of those killed. An extra Rs 2 lakh will be given from the Prime Minister's National Relief Fund, with Rs 50,000 for those with serious injuries.
Prime Minister Modi tweeted to say he had spoken to Mr Rawat, and said: "Am constantly monitoring the unfortunate situation... India stands with Uttarakhand and the nation prays for everyone's safety there." Home Minister Amit Shah also tweeted; he said the Modi government stood shoulder-to-shoulder with the people of Uttarakhand.
The NCMC (National Crisis Management Committee) met late Sunday evening and said information from the Central Water Commission (CWC) indicated there was no danger of downstream flooding at this point, and that the rise in water levels had been contained. There is also no threat to the neighbouring villages, the NCMC said after it met.
Medical teams have been rushed to affected sites. A 30-bed hospital was readied at Joshimath and hospitals in Srinagar, Rishikesh, Jollygrant and Dehradun are on standby.
Five NDRF teams were mobilised at first. By Sunday evening three more were deployed, with five tonnes of relief equipment, from Ghaziabad's Hindon Air Force base. Teams are also being airlifted from Dehradun to Joshimath. Two ITBP teams and several SDRF teams have also been mobilised. The Army has sent six columns, each with 100 soldiers, as well as medical teams and an engineering task force with earth-moving equipment. Seven Navy diving teams have also been deployed.
Videos and images showed the massive burst of water tearing through a narrow valley below the power plant, leaving roads and bridges destroyed in its wake. Authorities emptied two dams in a bid to stop the flood waters from reaching Rishikesh and Haridwar, where people were barred from going near the Ganga riverbanks.
Massive flash floods and landslides hit Uttarakhand's Kedarnath in June 2013 after a multi-day cloudburst. Over 5,700 people were killed in one of the country's worst natural disasters since the 2004 tsunami. The floods also damaged parts of the famous Kedarnath temple, which is located 3,581 metres above sea level.
Melting of Himalayan glaciers has doubled since the start of the 21st century due to rising temperatures, a study published in 2019 said. Scientists analysed 40 years of satellite observations across India, China, Nepal and Bhutan, which indicates climate change is eating Himalayan glaciers. This potentially threatens water supply for hundreds of millions of people in these countries, including India.
The Uttarakhand government has made the following helplines for the Disaster Operations Center available to those stuck in affected areas or in need of any help: 1070 or 9557444486
With input from AFP, ANI, PTI