Indian President Ram Nath Kovind has given his assent to the Citizenship (Amendment) Bill, 2019, turning it into a law amid violent street protests in Shillong where curfew was imposed in unrest-hit areas and a ban clamped on internet and SMS services.

According to an official notification issued late last night, the new law went into effect with its publication in the official gazette on Thursday.

According to the act, members of Hindu, Sikh, Buddhist, Jain, Parsi and Christian communities who have come from Pakistan, Bangladesh and Afghanistan till December 31, 2014 after facing religious persecution there will not be treated as illegal immigrants but will be given Indian citizenship.

The president's nod came after the Citizenship (Amendment) Bill was passed by Rajya Sabha on Wednesday and by Lok Sabha on Monday, reports our New delhi correspondent.

After vehicles were set on fire and vandalised in Police Bazaar and Duh localities, the Shillong district administration clamped curfew in areas under Sadar Police Station and Lumdiengjri Police Station, District Deputy Commissioner MW Nongbri said.

She said at least 20 localities were under curfew from 10 pm last night until further orders.

Reports said about 3o youths, armed with rods, went on the rampage setting cars on fire and attacking traders, shops and shoppers.

The Meghalaya government on Thursday withdrew mobile Internet and messaging services across the state for the next 48 hours due to deteriorating law and order situation triggered by protests over contentious Citizenship (Amendment) Bill, officials said.

Additional Home Secretary CV D Diengdoh issued the order after receiving inputs from the police and the district administrations across the state, they said.

Messaging platforms like SMS, WhatsApp and social media platforms like Facebook, Twitter and You Tube are likely to be used for transmission of information through pictures, videos and text that have the potential to cause civil unrest and exacerbate the law and order situation," Diengdoh said in the order

The violence in Shillong came on a day when curfew-bound Assam's biggest city Guwahati witnessed fresh violence during protests against the bill and two persons were killed in police firing.

Meghalaya Chief Minister Conrad K Sangma on Thursday postponed a scheduled meeting with Indian Home Minister Amit Shah as his cabinet colleagues failed to reach Guwahati airport in Assam to board a plane to Delhi, amid curfew and violent protests in the neighbouring state.

Sangma, who had managed to reach the airport, however, left for the national capital, official sources said.

"The CM had visited western Meghalaya earlier in the day. He took a separate route to reach the airport, on the outskirts of Guwahati. His cabinet colleagues, however, were stuck in violence-hit Guwahati," sources said.

Sangma is scheduled to meet Shah, along with his cabinet miniters, to seek total exemption of Meghalaya from the purview of the Citizenship (Amendment) Bill.

"The cabinet could not reach the airport on Guwahati outskirts due to curfew and anti-CAB protests in Assam. The chief minister had to fly alone. The scheduled meeting with Amit Shah tonight has been postponed till tomorrow," an official close to the Chief Minister's Office told PTI.

The ministers will leave for Delhi today by a chopper from Upper Shillong, he added.