Dr Singh, who is keeping a close watch on the situation, spoke to Home Minister Sushilkumar Shinde and Assam Chief Minister Tarun Gogoi and directed them to take urgent steps to restore normalcy in the disturbed areas, the PMO said.
Under PM's directions, Cabinet Secretary Ajit Seth held a review meeting with central and state authorities in New Delhi.
After the meeting, the PMO said 20 companies (approximately 2000 personnel) of central forces have been made available to the state and additional companies, including Cobra companies, will be sent as required.
Nine army columns have been deployed and patrolling is going on, it said.
Relief camps are being set up by the state government for those affected.
The Centre is standing by to provide food and medicines for the affected families as per the state's requirements.
The Prime Minister expressed "shock and grief" and said "such attacks are cowardly attempts to spread fear and terror among our citizens", the PMO said in a statement.
"Prime Minister Manmohan Singh has condemned the violence in Assam in which many a precious lives have been lost and a large number of people injured," the PMO said.
At least 32 people have been killed in violence unleashed by NDFB-Songbijit militants in Bodoland Territorial Administration Districts (BTADC) area in Assam.
Urging people to remain calm and ignore rumours, the Prime Minister said the central government and the state government will take all measures to maintain law and order and restore normalcy.
"The government stands committed to fighting terror in all its forms. The central government will assist the state government in taking all measures to defeat the forces of terrorism," the statement quoted him as saying.
"The people of Assam have been braving terrorist attacks with courage and fortitude in the past. They have voted in large numbers in the polling for the general elections and I am confident they will continue to fight terror resolutely," said Dr Singh who represents Assam in the Rajya Sabha and exercised his franchise there on April 24.
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