“We don’t rule out chances of more attacks and so have been taking further measures to avert it,” Home Affairs Minister Lutfuzzaman Babar said after meeting senior police and intelligence officials on Sunday.
No one has claimed responsibility for about 500 small-bomb explosions across the country on 17 August, which killed two people and wounded about 100.
But copies of a leaflet found at most bomb sites carried a call by banned group, Jamaat-ul-Mujahidin, for the introduction of Islamic rule in Bangladesh, a Muslim democratic country.
Police said many of those arrested confessed to being members of Jamaat-ul-Mujahidin and of being involved in the bombing attacks.
“They have given information suggesting that not only Islamic militants but other terror groups were also involved in the bombings,” Babar said.
“We are updating security everywhere, including plans to install close-circuit cameras at street corners.”