Indian police, meantime, confirmed they had detained a man in West Bengal but did not say whether he was the hunted Bangladeshi militant kingpin, reports Reuters.

State Minister for Home Affairs Lutfozzaman Babar told reporters yesterday afternoon that he came to know of the developments from local newspapers.

He said they are trying to be sure through the foreign ministry and diplomatic channels about what in fact has happened. But they have not got any such information confirming the reports yet.

Two Bangla and an English daily yesterday reported that police picked up Abdur Rahman, supreme leader of the banned Islamist militant group responsible for countrywide bomb blasts since August 17, from a hideout in Barasat on Sunday.

According to the media reports, the West Bengal police arrested Mohsin, an operative of the Islamist outfit, in the 24 Parganas a few days ago. Acting on information obtained from him, they conducted a raid in Barasat Sunday and arrested Rahman.

The Indian authorities had taken him to New Delhi for interrogation, the reports added.

"We have picked up a man on Sunday. We still are verifying the whole thing and who he is," Reuters quoted Inspector General of West Bengal police Raj Kanojia as saying over phone from Kolkata.

The police officer said the man was held in a southern district in West Bengal on Sunday but he did not confirm his nationality.

Private television channel ATN yesterday, however, reported that West Bengal Police do not have information of any such arrest. "Botia thana police said no one named Abdur Rahman has been arrested," ATN correspondent Samir Debnath reported from Kolkata.

After countrywide blasts on August 17 last year followed by suicide bombings in different districts, the government on October 28 declared a bounty of Tk 50 lakh for information leading to arrest of the JMB chief or his aide Siddiqul Islam alias Bangla Bhai. Earlier on September 11, the government had announced the bounty without mentioning the amount. Both the militant leaders have been spearheading a nation-wide campaign for establishing Islamic law in Bangladesh.

The government on February 23 the same year banned the JMB and Jagrata Muslim Janata, Bangladesh (JMJB), accusing them of carrying out a series of bomb attacks and killings to create anarchy.

The law enforcers in Bangladesh went into a massive operation in Kushtia last week on an intelligence that JMB top brass including Rahman and Bangla Bhai had been holed up there. But the operation regarded as the biggest ever failed to nab any of them.