Police said 55 homemade bombs and explosives packed in seven plastic containers and two glass bottles, six sharp knives, 51 wires, 28 wicks and four combatant belts were found in the family graveyard of Montajer Rahman, the fugitive leader of the extremist group.

Meanwhile, the officer investigating the August 14 firefight was relieved of his duty for "suspicious behaviour" and official sources said the militants were planning a major act of sabotage.

"The materials were found as nearly 100 policemen under an additional police superintendent were sweeping Uttar Moheshpur village for the looted arms and ammunition of the police and the cache of the outfit," a police officer said.

Police said they were near-sure the two were linked to the Dinajpur blast earlier this year and an investigation was underway to find their involvement in Joypurhat firefight.

The Detective Branch of police was given the charge to investigate the militant activities as hunt for the militants continued under a joint drive of police and paramilitary BDR.

The investigation officer of the firefight, also the officer-in-charge of the Khetlal Police Station, was relieved of his duty.

Officials said he was served with a show cause notice for neglect of duty and was likely to face action for his 'mysterious absence' in the police raid on Uttar Maheshpur village, defying specific orders.

A senior police officer of Joypurhat yesterday reasserted that they had evidence the militants were plotting a major act of sabotage when police raided the house of Montajer Rahman.

"We are now sure they were planning destructive activities in the night of the firefight," a senior police official said.

Police said they would continue searches in Uttar Moheshpur as they believed the militants left many things in the area.

Thakurgaon police said they believed the arrested suspects Fazle Rabbi, 22, and Lutfar Rahman, 44, were trainers of the outfit. They were held on Thursday from Rani Sankail in Thakurgaon district.

Police arrested Rabbi, a college student of Gaibandha, for his suspicious movement as he tried to flee the scene kicking a policeman after being asked about his identity.

Police arrested him chasing nearly four kilometres and later captured Latifur, a businessman, from a nearby place basing on Rabbi's statement.

Police said Rabbi was earlier held by locals in Hibildarpara in the area when he was imparting "training" to some 20 youths. But he was released with the intervention of one "influential man".

The pair is now being interrogated. "They have already given important information about their activities," a police official said.