A team of the FBI of the US met detectives in Dhaka on Sunday and offered their technical expertise.
Hoque said he alerted the chiefs of NIA and CBI against Chowdhury.
As many as 2,128 people have been arrested on the second day of a nationwide anti-terror crackdown, police said, adding 48 of them belonged to various militant outfits.
A British national and a student of a Canadian University have been arrested for their alleged involvement in Bangladesh's worst terror attack at a cafe in Dhaka last month that killed 22 people, including an Indian girl.
Bangladeshi-Canadian Tamim Ahmed Chowdhury and dismissed army officer Syed Md Ziaul Haque have been identified as the brains behind the two terror attacks.
The slain militants are believed to be members of Jamatul Mujahideen Bangladesh.
Rohan Ibne Imtiaz, the son of S M Imtiaz Khan Babul, a leader of the party's Dhaka City chapter and Bangladesh Olympic Association's deputy secretary general, has been identified as one of the attackers by another Awami League leader, BD News reported.
The increase in home-grown radicalised Islamic groups and the rise of Islamic State and Al Qaeda in Bangladesh should be a matter of worry for India, which shares a 4,100 km border with its eastern neighbour, says Rajeev Sharma.
The Bangladesh government on Sunday claimed the attackers who slaughtered 20 hostages inside a cafe in Dhaka in the country's worst terror attack were members of "homegrown" Islamist terrorist outfits and not Islamic State of Syria and Iraq militants.
Sheikh Hasina's government has launched a relentless war against terrorism since the Dhaka cafe carnage in July 2016, but as Bangladesh's terror networks exploit new technologies and new tactics, the challenge to eliminate jihad gets tougher, points out Binodkumar Singh.
