India's National Investigation Agency arrested two key members of Jama'atul Mujahideen Bangladesh (JMB) involved in the Burdwan blast of October 2014 from West Bengal on Monday.   

In a statement, the NIA said Kador Kazi alias Mijanur Rahman alias Harun Mandal, 32, and Sajjad Ali, 21, were arrested from an under-construction building in Hoogly district. They had pretended to be construction workers, the NIA added.

Kador was charge-sheeted in the case for his direct involvement in the militant outfit's conspiracy to wage war against the governments of India and Bangladesh in 2015. He had a reward of Rs 5 lakh on his head, the agency said.

READ MORE: JMB men behind Burdwan blast

During primary interrogation, Sajjad said he was an associate of Kador and was in touch with other accused JMB members through encrypted messaging apps, the NIA said, adding that materials for making improvised explosive devices (IEDs) were also seized from his possession.

Kador, known to be an explosive expert, and Sajjad, who is part of JMB's recruitment cell, were produced before a Kolkata court and it placed them on a 14-day remand.

Kador is the brother-in-law of JMB's India head Kausar alias "Boma" Mizan, who is a Bangladeshi national. Kador had been on the run since the Burdwan blast on October 1, 2014.

NIA sources said they wanted to question Kador in connection with the bomb blasts at Bodh Gaya, a revered Buddhist shrine in Bihar, on January 19 last year, in retaliation for alleged atrocities against Rohingyas in Myanmar. 

The NIA arrested Kador based on Mizan's information during the latter's interrogation, the sources added.

In the run up to the Burdwan blast, Kador had accompanied Mizan to buy explosives in Kolkata. Kador was also trying to establish the JMB network in Assam and mobilise funds for the outfit.

Meanwhile, the NIA said it filed a supplementary charge sheet against Kausar and five other JMB members on January 28 in the IEDs planting case at Bodh Gaya before the NIA special court in Patna.

On September 27 last year, a charge sheet accusing three was filed with the court in the Bodh Gaya blast case. The court took cognizance of the charge sheet.

The NIA said its probe revealed that Kausar, along with the other accused, formed a terrorist gang and hatched a conspiracy to carry out attacks on the Bodh Gaya temple and other symbols of Buddhist faith.

Investigation also established that the accused used fake and assumed names for travel and renting hideouts and used encrypted text for communication to conceal their real identities and the designs of the conspiracy to wage a war against the government.