Sheikh Hasina declared the next two days a period of mourning in the wake of the attack at a cafe frequented by foreigners in Dhaka.

At least 28 people were killed when armed militants stormed the cafe and took the customers and wait staff hostage on Saturday. Most of the victims were foreigners, including nine Italians and seven Japanese.

The militants hacked most of their victims with machetes, leaving their bodies to bleed over the floor. The so-called "Islamic State" (IS) militant group claimed responsibility for the attack, saying it was an attack on citizens from "crusader countries."

Hasina warned that such violent extremism could destabilize the country and turn it into a failed state. She also disavowed the militant's brand of Islam.

Hasina pleads for no more killing

"Islam is a religion of peace," she said in a televised address. "Stop killing in the name of the religion."

In Italy, Prime Minister Matteo Renzi expressed outrage at the killing of his countrymen. "The terrorists want to rip away the daily fabric of our lives," he said.

In total, 13 people were rescued. Security forces said their efforts to put an end to the seige were stymied by heavy gunfire and grenades.

Two police officers were also killed in the ensuing violence.

Wide-ranging probe launched in killing's wake

Many details of the attack remain unclear. Police released photographs of the bodies of five attackers, along with their first names: Akash, Badhon, Bikash, Don and Ripon.

"They are all Bangladeshis. They are from rich families, they have good educational background," Bangladesh's Home Minister Asaduzzaman Khan said.

Investigators say the men's families say they had had no contact with the men for months.

"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.

International link?

That would suggest an international link to the carnage, despite the government insisting that a wave of Islamist violence over the past 18 months is the work of homegrown militants rather than admit that international jihadists have a presence in the South Asian country.

"Pictures (uploaded on Twitter) indicate they might have been encouraged by ISIS ('Islamic State') activities abroad," said Muhammad Zamir, a former senior Bangladesh foreign ministry official. "But this does not show a direct link to ISIS. This is exactly what was done and disputed later in the case of the Orlando attack."

Survivors say the gunmen singled out foreigners as soon as they stormed through the doors of the restaurant popular with expatriates. They ordered all Bangladeshis to stand up before the killing began, a source briefed on the investigation said. The Bangladeshis were later told to close their eyes and recite verses from the Koran.

The Islamic State-affiliated Amaq news agency claimed in a report on Saturday that the militants identified and released Muslim patrons from the Dhaka restaurant, SITE said.

The victims also included at least three Bangladeshis or people of Bangladeshi descent.

blc,jar/bw (AFP, Reuters)