New Delhi, June 17 : President Ram Nath Kovind on Wednesday expressed the nation's gratitude to 20 Indian soldiers who died in a violent face-off with China's People's Liberation Army (PLA) troops in Ladakh's Galwan valley, saying they sacrificed their lives to protect the sovereignty and integrity of the country. "As Supreme Commander of the Armed Forces, I bow to the exemplary courage and supreme sacrifice of our soldiers to protect the sovereignty and integrity of the country," Kovind tweeted. Vice President M. Venkaiah Naidu also said the nation will forever be indebted to the soldiers for their supreme sacrifice. "My deepest condolences to the families of these Veer (brave) jawans," Naidu tweeted. At least 20 Indian soldiers, including a commanding officer, were killed at Galwan valley in eastern Ladakh during a face-off between Indian Army and the Chinese troops on Monday night. Around 120 Indian soldiers, almost an entire company, were trapped by PLA troops who savagely attacked them, many to the point of mutilation, on Monday night at the patrolling point number 14 on the Line of Actual Control (LAC) in eastern Ladakh. The Indian Army on Tuesday said 20 of its men, including an officer, were killed in an unprecedented violent clash with PLA. The force said the death toll would increase, as many soldiers were grievously injured. In a statement, the Indian Army stated that 17 Indian soldiers who were critically injured in the line of duty at the stand-off location and exposed to sub-zero temperatures in the high altitude terrain have succumbed to their injuries, taking the death toll to 20. /IANS