Decoding reason behind Uttarakhand glacier burst

Uttarakhand Chief Minister Trivendra Singh Rawat, who visited Chamoli in wake of the deluge following a glacier burst on Sunday, said that over 125 people are missing and the number is likely to rise further.

What is the reason behind the incident? 

Prime Minister Narendra Modi on Sunday announced Rs 2 lakh ex-gratia for next of the kin of all those who have lost their lives in the massive flash flood caused by a glacier breach near Joshimath in Uttarakhand's Chamoli district.