He is survived by wife and a daughter. Wheelchair-bound Britto was a writer who had been active in the cultural and political circles in Kerala, they said.
The Kochi-based politician was nominated as the Anglo-Indian representative during the term of the Left Democratic Front government from 2006 to 2011.
In 1983, he became the vice-president of the SFI (Kerala). He suffered paralysis in his lower body during a violent clash between student unions.
Badly wounded in the clash, he was a constant reminder of the violent campus politics of the 1980s.
Even after the attack, Britto was active in mainstream politics.
Kerala Chief Minister Pinarayi Vijayan condoled the demise of Britto.
'Extremely saddened to learn of the passing away of comrade Simon Britto. He was one of the finest political leaders of this generation,' the chief minister said in his condolence message.
A source of limitless inspiration, Britto's death is an irreparable loss to the political and cultural life of Kerala, he added.
In his condolence message, CPI(M) general secretary Sitaram Yechury said, "In the loss of Simon Britto, we have lost a leader who people could look up to for inspiration."
Yechury said he had known Britto since their days in the SFI.
Recalling the shock and anguish with which he had received the news of the brutal attack on Britto, Yechury said though given up for dead, Britto, true to his spirit, bounced back to life.
"He (Britto) fought valiantly and after years of treatment was able to lead a life of dignity. Despite his disability owing to the brutal attack, he continued to contribute to the movement in various ways. His commitment was unwavering.
"His courage and determination are an example that will have to be emulated by the generation of today," he said.
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