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Assam Chief Minister Sarbananda Sonowal was among those stuck at Guwahati Airport as the situation spiralled out of control in the state's largest city. Mr Sonowal's security detail, however, managed to take the Chief Minister to his residence through the city, parts of which resembled a warzone.
In Guwahati police fired blank shots, tear gas shells and lathi-charged protesters, a majority of them students, in different parts of the city as thousands of demonstrators attempted to barge past security barriers.
Police opened fire on protesters in the state capital of Dispur to quell protests after water cannons, baton- and lathi-charges and the use of tear gas failed to rein them in.
Student protesters in Guwahati also damaged a roadside stage erected for Prime Minister Narendra Modi's proposed summit meeting with his Japanese counterpart Shinzo Abe on Sunday, PTI reported.
In a rare show of solidarity with the protesters government employees at the secretariat wore ''gamosa'' (Assam's state symbol of honour), stood behind the gates and
chanted slogans against the CAB.
Senior civil and police officials are incommunicado but, according to unofficial accounts, hundreds of protesters have been detained in Guwahati and other places like Dibrugarh and Jorhat, news agency PTI reported.
In neighbouring Tripura the Congress has called for a state-wide shutdown on Thursday. The state government, on Tuesday, had blocked mobile internet and SMS services across the state for 48 hours. A two-month-old baby died while being taken to a hospital in Sepahijala as protests blocked traffic, police said.
The clampdown came as demonstrators raised slogans against the centre in Agartala, demanding the state be kept out of the purview of the bill. Earlier, protesters set fire to a market with shops mostly owned by non-tribals in the northeast state's Dhalai district.
Last week Union Home Minister Amit Shah, who led the centre's push on the Citizenship (Amendment) Bill in the Lok Sabha on Monday and did so again in the Rajya Sabha on Wednesday, held extensive meetings with stakeholders in the North East, saying appropriate exceptions had been made and urging protesters to stand down. Following on from those meetings the draft version of the Citizenship Bill excludes tribal areas of Assam, Tripura, Meghalaya and Mizoram, as well as the area under "The Inner Line" permit system.
The Citizenship (Amendment) Bill, 2019, seeks to grant Indian citizenship to non-Muslim refugees from Pakistan, Bangladesh and Afghanistan if they faced religious persecution there. It also allows the government to cancel registrations of Overseas Citizen of India (OCI) cardholders who violate provisions of the bill "or any other notified law".
With input from PTI