Tributes are pouring in for Sitaram Yechury, a veteran leader of the Communist Party of India (Marxist), or CPI(M), who passed away on Sept 12 at the age of 72 after battling a prolonged illness.

The veteran Communist leader was in a critical condition and had been receiving respiratory support at the All India Institute of Medical Sciences in New Delhi. According to CPI(M) leaders, Yechury was being treated in the hospital's intensive care unit for acute respiratory tract infection. Over the past few days, he had been under treatment by a multidisciplinary team of doctors.

Born on Aug 12, 1952, Yechury was serving as the general secretary of the CPI(M) since 2015. He was a member of the Politburo of the CPI(M) since 1992. Earlier, he was a member of India's parliament from 2005 to 2017.

China's Ambassador to India Xu Feihong expressed sorrow at Yechury's passing, remembering him as "a staunch Marxist and an old friend of the Chinese".

"Deeply saddened by the passing of Comrade Sitaram Yechury, General Secretary of the Communist Party of India (Marxist). My deepest condolences to his family and comrades of CPI(M) during this difficult time. He is a staunch Marxist and an old friend of the Chinese people. His contribution to China-India relations and friendship will be remembered forever," Xu said in a post on the social media platform X.

The Polit Bureau of the CPI(M) also paid a heartfelt tribute to their comrade, saying in a statement that he was an outstanding leader of the Left movement and a well-known Marxist ideologue.

Yechury's passing marks the end of an era for the CPI(M), where he was known for his unwavering commitment to Marxist principles and his ability to engage in thoughtful dialogue with political adversaries.

"The untimely demise of Sitaram Yechury at this crucial juncture in our national politics is a big blow for the CPI(M) and a grievous loss for the Left, democratic and secular forces. The Polit Bureau pays respectful homage to our beloved colleague and dips the red banner in his memory. The Polit Bureau calls upon all Party ranks to unite and work harder to advance the struggle for an exploitation-free society," it said.

"He was a brilliant student who secured a first class in both his undergraduate and post-graduate degrees in economics. He joined the student movement in Jawaharlal Nehru University in 1974 and became a leader of the Students Federation of India. He was the All India President of the Students Federation of India from 1984 to 1986 and played an important role in developing the student organization as an all-India force," the CPI(M) Polit Bureau said in the statement.

Indian President Droupadi Murmu, in her condolence message, praised Yechury's "distinct and influential voice". "Though a committed ideologue, he won friends cutting across the party lines. My heartfelt condolences to his family and colleagues," she said.

Prime Minister Narendra Modi also offered his condolences, noting that Yechury was a "leading light of the Left" and "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," the PM said in a post on X.

Political leaders cutting across party lines mourned the passing of the veteran Marxist leader.

Sitaram Yechury "was a friend and a protector of the Idea of India, possessing 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," Indian National Congress, or INC, leader Rahul Gandhi posted on X.

"I am deeply aggrieved by the demise of Comrade Sitaram Yechury. Sitaram was one of the most outstanding leaders of the Left & Communist movement in contemporary times," Communist Party of India General Secretary D Raja said in a post on X.

Yechury started his political career as a student leader with the left-wing Student Federation of India. He was arrested during the Emergency in 1975, when the Congress government led by former Indian prime minister Indira Gandhi enforced a widespread restriction on civil freedom.

He played an important role during the peak years of federal government's coalition politics when keeping together divergent agendas and ideologies essential to the stability of India's federal government. In 1996, he was a key figure in the formation of a 13-party coalition that ruled India for almost two years.

In 2004, Yechury's party won a historic 44 seats in the parliamentary election.

The Left parties, which include the CPI(M), subsequently provided "outside" support to help form an INC-led government. "Outside support" was a proposal was put forth by Yechury at that time for endorsing the administration without joining the government or taking up any ministerial positions.

Yechury is survived by his wife Seema Chishti, son Danish and daughter Akhila.

The writer is a freelance journalist for China Daily.