Lok Janshakti Party (LJP) MP Ram Chandra Paswan, the younger brother of Union minister Ram Vilas Paswan, passed away at RML Hospital here on Sunday.
LJP MP Chirag Paswan, son of Ram Vilas Paswan, tweeted, "With great sadness, I inform you that my uncle Ram Chandra Paswan is no longer with us. He took his last breath at around 1:24 pm at Ram Manohar Lohia Hospital in New Delhi."
Ram Chandra Paswan, 57, had suffered a massive heart attack on Thursday and was admitted to the hospital.
Condoling the death, Prime Minister Narendra Modi said on Twitter, "Shri Ram Chandra Paswan Ji worked tirelessly for the poor and downtrodden. At every forum, he spoke unequivocally for the rights of farmers and youngsters. His social service efforts were noteworthy. Pained by his demise. Condolences to his family and supporters. Om Shanti."
Bihar Chief Minister Nitish Kumar also mourned the LJP MP's "untimely demise" and announced that the last rites will be performed with state honours.
"Ramchandra Paswan was a good leader and well known social reformer. He was simple, sociable and very popular in his constituency. His demise is an irreplaceable loss for both society and politics. His last rites will be performed with state honour," Kumar said in the statement.
( With inputs from ANI )