As the death toll mounted to 62 in the four attacks by NDFB(S) militants in Assam's Sonitpur and Kokrajhar districts, angry Adivasi villagers today retaliated by setting ablaze houses of Bodos and took out protest marches.

Chief Minister Tarun Gogoi said that the majority of victims in the "barbaric" attacks that took place last evening were women and children and steps were being taken to ensure that the situation does not escalate. The Centre said it was rushing in 5000 paramilitary personnel at the request of Assam government.

IGP (Law and Order) S N Singh told PTI that the death toll had risen to 62 with 37 deaths in Sonitpur and 25 in Kokrajhar after heavily armed militants belonging to the Songbijit faction of National Democratic Front of Bodoland (NDFB) swooped down on the four remote Adivasi villages of the two districts and killed the inhabitants last evening.

In Sonitpur district, 31 people were killed in Maitalu Basti under Zinzia police station and six in Jungle basti under Dhekiajuli police station while 20 people were killed in Shantipur Ultapani under Kokrajhar police station and five in Pakhriguri under Serfanguri police station of Kokrajhar district, he said.

Search operations were continuing in these interior villages which lack proper road communication.

Meanwhile, angry protestors, belonging to the Adivasi community set ablaze five houses allegedly belonging to the people of the Bodo community in Phuloguri area under Bishwanath Chariali police station in Sonitpur district Protest rallies were also taken out by thousands of tea garden workers, armed with bow and arrows, and a seven-km stretch of National

Highway 15 was blocked by the protestors near Dhekiajuli in Sonitpur.

Indefinite curfew was clamped tonight in four police station areas of Sonitpur district.

"Indefinite curfew has been clamped in the areas in the jurisdiction of Dhekiajuli, Thelamara, Rangapara and Biswanath Chariali police stations," Deputy Commissioner of Sonitpur district, Lalit Gogoi said.

Union Minister Rajnath Singh, who will be going to Assam later in the day, said he has been briefed about the situation by Chief Minister Tarun Gogoi and necessary action will be taken by the Centre.

"I will travel to Assam today and review the sitation there. Whatever action is required, we will take," he told reporters in Delhi.

The Centre is mobilising 50 companies (5000 personnel) of central forces at the request of Assam, Minister of State for Home Kiren Rijiju said.

"It is unfortunate that this kind of violence has taken place when we have already sent a message that violence and development cannot go together," he said.

Gogoi said he has directed senior ministers Nilamani Sen Deka and Basanta Das to go Kokrajhar district and Rockybul Hussain, Prithbi Majhi and Tanka Bahadur Rai to visit Sonitpur district.

Prime Minister Narendra Modi condemned the killing of innocent people as an act of cowardice. "Our thoughts and prayers are with the families of the deceased," he tweeted.

Modi said he spoke to Assam Chief Minister Tarun Gogoi and Union Home Minister Rajnath Singh. "Rajnath ji will travel to Assam and take stock of the situation," he said. Singh said killing of innocent people for any cause can never be justified.

A group of NDFB(S) militants with sophisticated arms fired at people in Sonajuli under Biswanath Chariali sub-division in Tinisuti near the Arunachal Pradesh border, she said.

In this attack, 24 persons were killed and six others injured, she said.

The incident site is located very near to the inter-state border between Assam and Arunachal Pradesh.

Meanwhile, Manas National Park, a popular tourist spot inhabited by many tribals, has been closed for three days in the wake of killing by NDFB(S) terrorists today of at least 34 people in serial attacks in two districts of Assam.

"We have shut Manas National Park for three days.

There are lots of Adivasi and tribal people staying near the Park," Baksa district Deputy Commissioner Vinod Seshan said.

Manas National Park, known for its rich natural beauty, primarily falls in Baksa district.

"Also, many tea gardens are located in the nearby area where thousands of people belonging to tea tribe resides," Seshan said.