Mr Gurung also convened an emergency meeting of the GJM leadership to expel Mr Tamang and another member, Mr Anit Thapa, from the party.
Since yesterday night, protests in support of carrying forward the shutdown have rocked several parts of the hills.
Rallies supporting the indefinite bandh were taken out in Darjeeling, Kurseong, Mirik, Sonada and Kalimpong last night.
Confusion prevailed among the people of the hills over the differences within the GJM. When some traders tried to open theirs shops, GJM supporters forcibly closed them, the police said.
The party leadership claimed that a woman was killed during lathi charge by police to disperse a crowd that was protesting against the decision to suspend the shutdown. The police, however, denied the allegation.
Mr Tamang's house, meanwhile, was ransacked by pro-Gorkhaland supporters. Posters were pasted in front of his house terming him a "traitor of Gorkhaland".
An indefinite strike had been continuing in the hills since June 15 demanding a Gorkhaland state. The strike has entered the 79th day today.
Mr Gurung also slammed Mr Tamang as a "traitor" who was playing into the hands of the state government.
"He has been removed as party convenor and a central committee meeting has been convened to decide on whether to expel him from party," he said.
The next round of talks between the state government and the GJM is scheduled to be held in North Bengal on September 12.
The GJM has plans to take out rallies in various parts of the hills during the day, GJM sources said.
The police and security forces are maintaining a strict vigil in order to avoid any untoward incident.
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