A former leader of the Jatiya Samajtantrik Dal or JaSoD, the septuagenarian breathed his last at the Asgar Ali Hospital around 4pm on Friday, his brother Manjur Ahad Helal, a retired army officer, said.
Sumon tested negative for COVID-19 twice as the doctors had initially suspected he had been infected with the novel coronavirus.
Sumon was involved with the Bhorer Kagoj since its inception.
He had joined NTV briefly at the middle of his career but took charge as a joint news editor after his return to the Bhorer Kagoj, its Editor Shyamol Dutta told bdnews24.com.
Sumon is survived by his wife and two children.
JaSoD President Hasanul Haq Inu and General Secretary Shirin Akhter have offered their condolences to Sumon's family.
Sumon was a Chatra League leader in the early 60s. He was an organiser during the Liberation War.