The army, paramilitary forces and the state police on Tuesday braced for a joint offensive against the ULFA in Assam, with Defence Minister A K Antony saying 'no quarter' would be given to the banned group that has killed 69 migrant workers since Friday.

Despite steps taken by the authorities to protect Hindi- speaking migrants, they continued to flee from Assam for the second consecutive day on Tuesday even as the ULFA carried out a bomb blast at the police station in the capital complex of Dispur.

"The ULFA will not be able to carry on with its heinous crimes and no quarter will be given to them," Antony said after chairing a meeting with Chief Minister Tarun Gogoi, army chief General J J Singh and top commanders to review the situation in the state.

Expressing the government's determination to counter the ULFA's 'provocative killing' of civilians, Antony said a joint operation would be launched soon to strike at new bases of the group.

He promised all help to Assam, including troops and materials, to contain the upsurge in violence.

The army has re-deployed 3,500 troops from Misa in Arunachal Pradesh to Sibsagar and Dhemaji districts, where many Hindi-speaking people were gunned down.

General Singh said these troops will replace paramilitary forces in the area.

Another 10,000 army troops have been deployed in other violence-hit areas like Tinsukia and Nalbari, and the Centre decided to rush 1,000 more paramilitary forces to Assam to intensify operations against the ULFA.

The Centre had deployed 20 companies of central forces or about 2,000 men on Monday. 

"In the next few weeks, a joint operation will be carried out against ULFA cadres," Antony said after emerging from the hour-long meeting.

Both Antony and Gogoi said the 'doors were still open' for the ULFA to come to the negotiating table if it abjured violence and came forward for talks unconditionally.

Antony said the joint operations by security forces will target new hideouts created by ULFA cadres at Tinsukia and Dibrugarh in upper Assam and other areas.

The Centre will take up the presence of ULFA leaders in Bangladesh and Myanmar with authorities in those countries, he said.

Antony also admitted that the ULFA had used the peace process initiated by the People's Consultative Group and a brief ceasefire offered by the Centre last year to regroup.

Assam Police chief R N Mathur said the ULFA had some 2,500 new recruits and set up new camps in Arunachal Pradesh and Meghalaya.

Gogoi said he had never supported the release of jailed ULFA leaders as demanded by the group as a pre-condition for talks.

Both Gogoi and Antony said they would be 'more careful' in dealing with the proscribed group.

Earlier, Gogoi said the ULFA carried out the killing of non-Assamese migrants at the instructions of Pakistan's ISI.

"The countries (Pakistan and Bangladesh) where the ULFA leaders are taking shelter do not want peace in Assam. The ULFA is also not interested in peace talks," he said.

The security situation and Central forces needed to protect non-Assamese people will be reviewed at a high-level meeting to be chaired by Home Secretary V K Duggal in Delhi on January 12.