Seven militants who killed 20 people at a restaurant in Dhaka were local Bangladeshis and authorities had tried before to arrest five of them, police said, as investigators probed for possible links with international Islamist extremist groups.
The gunmen stormed the upmarket restaurant in the diplomatic zone late on Friday, before killing mostly non-Muslim hostages, including at least nine Italians, seven Japanese and an American.
Islamic State claimed responsibility, warning citizens of "crusader countries" that their citizens would not be safe "as long as their aircraft are killing Muslims", the group said in a statement. It also posted pictures of five fighters grinning in front of a black flag who it said were involved in the attack, according to the SITE monitoring website. The claims have not been confirmed, but Bangladesh Home Minister Asaduzzaman Khan told Reuters late on Saturday that neither Islamic State nor al Qaeda was involved. He reiterated the government's line that home-grown militants were responsible for a spate of killings in the country over the past 18 months.
"This was done by JMB," Khan said, referring to Jamaat-ul-Mujahideen Bangladesh, which claims to represent Islamic State in Bangladesh.
Analysts say that as Islamic State loses territory in Iraq and Syria and its finances get drained, it may be trying to build affiliates in countries such as Bangladesh for jihadists to launch attacks locally and cheaply.
Deputy inspector general of police, Shahidur Rahman, told Reuters on Sunday authorities were investigating any connection between the attackers and trans-national groups such as Islamic State or al Qaeda.
