Ram Vilas Paswan had a heart surgery just days ago in Delhi.
Ram Vilas Paswan -- minister in Prime Minister Narendra Modi's cabinet and the founder of the Lok Janshakti Party -- died on Thursday at a Delhi hospital where he was recuperating from heart surgery. The 74-year-old was undergoing treatment at the hospital, and had to undergo surgery last Saturday "due to the situation that had suddenly emerged," his son Chirag Paswan had tweeted on Saturday.
On Thursday evening, the 37-year-old posted the news of his death.
"Papa... Now you are not in this world but I know you are always with me wherever you are. Miss you Papa," read his post, with which he shared a throwback photograph with his father.
Home ministry officials said state funeral will be accorded to Ram Vilas Paswan and the national flag will fly at half-mast in Delhi and state capitals on Friday as mark of respect. Cremation will take place in Patna on Saturday.
Twitter was flooded with tributes for the departed leader. Among the first to tweet was President Ram Nath Kovind, PM Modi, Congress's Rahul Gandhi, BJP leader Ravi Shankar Prasad.
"I am saddened beyond words. There is a void in our nation that will perhaps never be filled. Shri Ram Vilas Paswan Ji's demise is a personal loss. I have lost a friend, valued colleague and someone who was extremely passionate to ensure every poor person leads a life of dignity," PM Modi's post read.
Known as one of the great survivors in Indian politics, Ram Vilas Paswan has been a minister in almost all Central governments formed since 1989 and served six Prime ministers, starting with the cabinet of VP Singh. In PM Modi's cabinet, he was in charge of the Consumer Affairs, Food and Public Distribution portfolios.
Ahead of the 2004 elections, Sonia Gandhi, with her famous "walk next-door", got him as an UPA ally.
A decade later, he was back with the BJP, even though he had broken ties with the party earlier citing the 2002 Gujarat riots. In 2014, when PM Modi, as the BJP's prime ministerial candidate, was looking for new allies, Mr Paswan dropped Lalu Yadav's Rashtriya Janata Dal to stitch an alliance with the BJP.
A powerful Dalit leader from Bihar, Mr Paswan was among the young leaders -- along with Lalu Yadav and Nitish Kumar -- who were inspired and nurtured by the JP movement in the '70s.
He was jailed during the 1975 Emergency and made his way into record books for the 1977 parliamentary elections, when he won from the Hajipur Lok Sabha seat in Bihar with the highest-ever margin.
Last year, Mr Paswan skipped the Lok Sabha polls, passing his Hajipur seat to his younger brother and Bihar minister Pashupati Kumar Paras and entered parliament through the Rajya Sabha.