KATHMANDU - The vice-chairman of Nepal's main opposition party UCPN (Maoist) has passed away Monday morning while undergoing treatment in a Kathmandu-based private hospital, sources said.

Post Bahadur Bogati, who passed away at around 6 am, had been admitted to the hospital last Thursday following a severe heart attack as well as brain hemorrhage. He was hospitalized and underwent a major surgery at Kathmandu-based Gangalal National Heart Center before being shifted to Norvic Hospital.

Norvic Hospital had said Bogati's condition had been critical on Sunday and had been put under ventilator.

Planning were also being made to airlift the 62-year-old leader to India for advance treatment.

Bogati had been an active member of Nepal's UCPN (Maoist) party since its foundational days.

Though the UCPN (Maoist) is yet to declare his death formally, the party's senior leader, Dr Baburam Bhattari, has announced his death through twitter. "It is very sad that Comrade Post Bahadur has passed away this morning. Condolence to the bereaved soul," he stated in a tweet.

According to party officials, the UCPN (Maoist) is now holding a meeting to decide how the final mourning of the deceased leader would be organized.