Followers of JMJB chief Abdur Rahman Shai and members of the JMJB bomb squad carried out the attacks, said the arrestee, Shafiqullah.

The bomb attacks were planned at a meeting at a madrasa in Jamalpur Sadar upzila, said Shafiqullah, arrested with explosives from JMJB operative Joynal's house at Chaksadu village of Gabtali upzila on January 16. He however claimed he was not involved in any bomb attacks.

"A jatra show at Chhantia village of Dikpite union in Sadar upazila was attacked to frighten people to restrain them from staging such shows," Shafiqullah was quoted as saying during police interrogation before he was sent to the Joint Interrogation Cell on Thursday.

JMJB operatives exploded two bombs in the attack leaving at least 15 people injured.

Activists of the militant outfit had made a similar attack on a jatra show at Gabtali bazar in Bhatra union under Sarisabari upzila that left around 10 people injured, the arrestee said.

The bombs were hurled from speeding motorbikes, he said, adding that he was not linked to any of the attacks.

Police however arrested Awami League (AL) activists and supporters in connection with the incidents.

Asked about the August 21 grenade attack on an AL rally in Dhaka, Shafiqullah told police that he knew nothing about it. " JMJB men were involved in most of the bomb attacks carried out across the country, and no grenade attacks," he said.

According to police, the arrestee said members of JMJB bomb squads have specified jobs. His task was to connect electric device to bombs and switches of remote control bombs.

The squads comprise separate people to hurl bombs and supply bomb-making materials. But he does know the identity of the others, he said.

JMJB chief Abdur Rahman, its operation commander Bangla Bhai and other top leaders could provide information on the other bomb attacks in different places in the country, Shafiqullah told police.

On Rahman's whereabouts, Shafiqullah only said he sometimes visits the madrasa at his village home in Jamalpur.

Meanwhile, in an interview with journalists at a government office at Bagmara in Rajshahi a few months back, Rahman said he returned to his Jamalpur home about seven years ago after his retirement from Bangladesh embassy in Saudi Arabia.

Claiming himself as a follower of Osama bin Laden, Rahman said he planned to form an organisation in 1997 along with some others having the same ideologies, and it came into being as Jama'atul Mujahidin.

Police raided a meeting of the organisation at Maheshpur of Khetlal upazila under Joypurhat district before it was formally launched, where Siddiqur Rahman alias Bangla Bhai was also present, Rahman told journalists

As the situation changed, the organisers changed the name of the organisation to JMJB, he said.

A top official of Bogra police said the operatives, involved in the bomb attack on a jatra show in Laxmikola village on January 14 that killed one and injured 40, are yet to be arrested.

Police are hunting for JMJB operatives -- Joynal, Osman and Wajed alias Mamun of Gaibandha -- believed to be involved in the attack, said the police official.