The Jamayetul Mujahideen Bangladesh (JMB) was accused of carrying out the serial blasts in Muslim-majority Bangladesh on August 17, 2005, prompting the then government to launch a nationwide manhunt.

Authorities said large-scale arrests of JMB guerrillas have blunted its influence.

"The group now poses no real or alarming threat as it has been under control since the executions of its leaders," said the security head of Bangladesh's Rapid Action Battalion.

"We have successfully combated them. There has hardly been any bomb attack in the past two years and we have arrested a lot of its members," Hasan Mahmud Khandaker said.

At least 1,000 JMB members have been arrested and almost all its top figures hunted down, Khandaker said.

Rebel leader Shaikh Abdur Rahman and his deputy Siddiqul Islam Bangla Bhai are in state custody, while six senior rebels were executed last year after a court sentenced them to death for slaying two judges.

The security force launched the crackdown following criticism that Dhaka was turning a blind eye to growing extremism.

Khandaker said a mop-up operation was on to arrest remaining guerrillas.

"They have not been wiped out yet, but they are very much under control," the officer said.

Khandaker's claim came after the Bengali-language newspaper Prothom Alo warned the JMB was regrouping.

The group says the bomb attacks were aimed at replacing Bangladesh's colonial British-era legal system with Islamic Sharia law.