Photographs of the terrorists released by the ISIS appear to tally with the terrorists gunned down by the security forces after an 11-hour siege.
Most of the terrorists who attacked Dhaka's Holey Artisan Bakery on Friday were mostly from well-to-do families and went top schools and universities in Dhaka, Information Broadcasting Minister Hassanul Haq Inna has told NDTV.
Most of them were in their early 20s and were on the police watch list. "Had the police got them, this attack could have been prevented," he told NDTV.
The arrested terrorist, the minister said, is yet to be questioned. "He is injured and the police have not been able to interrogate him," Mr Haq said.
Explaining the background of the terrorists - who had slaughtered 20 people, including Indian student Tarishi Jain and 17 foreign nationals -- the minister said some of them went to posh schools, like Scholastica, and costly private university like North South University in Dhaka.
"Of course, the institutions or the schools aren't to blame, but it is a new thing," he said.
Asked who could be responsible for the attack, he said, "While it too early to come to a conclusion, Bangladesh has historically seen terror originating from Jamaat-e-Islami.
Local groups backed by Jamaat propped up by Pakistan have sponsored numerous attacks, including recent ones," he said
Dhaka's policy, he said, is clear. "We do not and will not negotiate with terrorist or with their mentors.