Sitaram Yechury was suffering from a pneumonia-like infection.
Veteran Left leader and CPI (M) General Secretary Sitaram Yechury died this afternoon after battling pneumonia. The veteran leader was 72 and was admitted to Delhi's All India Institute of Medical Sciences (AIIMS).
The CPM leader was admitted to the emergency ward of AIIMS on August 19 and later shifted to the Intensive Care Unit (ICU). AIIMS said Sitaram Yechury was admitted to the hospital with pneumonia and he died at 3:05 pm today. The hospital said Mr Yechury's family has donated his body to AIIMS, New Delhi for teaching and research purposes.
Prime Minister Narendra Modi mourned the veteran leader's death and said, "Saddened by the passing away of Shri Sitaram Yechury Ji. He was a leading light of the Left and was known for his ability to connect across the political spectrum. He also made a mark as an effective Parliamentarian. My thoughts are with his family and admirers in this sad hour. Om Shanti."
"Saddened to learn about the demise of CPI (M) general secretary Shri Sitaram Yechury. First as a student leader and then in national politics and as a parliamentarian, he had a distinct and influential voice. Though a committed ideologue, he won friends cutting across the party lines. My heartfelt condolences to his family and colleagues," President Droupadu Murmu said.
Defence Minister Rajnath Singh remembered Sitaram Yechury and said, "In his long years in public life, he distinguished himself as a seasoned parliamentarian who was known for his knowledge and articulation," adding, "He was also my friend with whom I had several interactions. I will always recall my interactions with him. Condolences to his bereaved family and supporters. Om Shanti!"
Leader of Opposition in Lok Sabha, Rahul Gandhi, said, "Sitaram Yechury ji was a friend. A protector of the Idea of India with a deep understanding of our country."
"I will miss the long discussions we used to have. My sincere condolences to his family, friends, and followers in this hour of grief," Mr Gandhi said.
"I express my condolences on the demise of senior politician and former MP Shri Sitaram Yechury. May God grant peace to the departed soul and give courage to the family to bear this loss," Lok Sabha Speaker Om Birla said.
Union Road Transport and Highways Minister, Nitin Gadkari, said Mr Yechury's "contributions to public life will always be remembered".
"Heartfelt condolences to his family and loved ones during this difficult time. Om Shanti," Mr Gadkari added.
"I am deeply saddened by the tragic demise of veteran CPM leader, Sitaram Yechury ji. We had many years of working relations in the Parliament. Extending my deepest condolences to his family, colleagues and admirers," Union Minister Kiren Rijiju mourned the veteran leader's death.
"Sad to know that Sri Sitaram Yechury has passed away. I knew the veteran parliamentarian that he was and his demise will be a loss for the national politics," West Bengal Chief Minister Mamata Banerjee said.
"I express my condolences to his family, friends and colleagues," Ms Banerjee said.
"The demise of CPI (M) General Secretary and senior leader Sitaram Yechury ji is an irreparable loss to Indian politics," Congress said.
"May God give place to the departed soul in his lotus feet and give strength to the bereaved family to bear this sorrow," the party said.
A member of the Politburo, CPM's top decision-making body, for over three decades, Mr Yechury was a member of the Rajya Sabha from 2005 to 2017.
An alumnus of Delhi's St Stephen's College and Jawaharlal Nehru University, Mr Yechury started his political career with the Students' Federation of India and joined the CPIM in 1975. He was pursuing his doctorate in Economics from JNU when the Indira Gandhi government imposed the Emergency in 1975 and he was arrested along with many other leaders who would later play a key role in national politics. His PhD remained incomplete.