Some civilians died during a siege in the Bangladeshi capital where troops stormed a restaurant and killed six extremists holding hostages, the prime minister said Saturday.
Sheikh Hasina said the commandos had rescued 13 hostages and captured one of the extremists.
"We were able to rescue 13 people alive, and could not save a few lives," Hasina said.
Exact casualty figures and other details would be revealed in an official briefing in the afternoon, officials said.
Police officer Hafizur Rahman said the operation ended within an hour after the troopers burst into the building in Dhaka's diplomatic district to rescue the victims on Saturday morning.
Gunshots and two loud explosions were heard.
The surviving hostages sent to hosptials for treatment included some foreigners.
Five bodies of slain attackers were seen on the floor of the restaurant, he said. The military was preparing to give an official briefing soon.
Earlier reports said there were nearly two dozen hostages held by about eight to 10 attackers that took the cafe Friday night.
The gunmen entered the Holey Artisan Bakery at about 8:45 pm as customers were eating in the upscale Gulshan area. The attackers killed two police officers in an initial exchange of gunfire, and a tense standoff carried into the morning as attempts to negotiate a solution failed.
Foreign hostages including Italians and Japanese, diplomats said.
"No acts of terrorism will be tolerated in Bangladesh," the prime minister said, urging citizens to unite against extremism.
An online media outfit allied with the Daesh organization reportedly claimed responsibility for the attack.
Other reports said American officials suspected al-Qaeda in the Indian subcontinent, which the US declared a 'terrorist' group the day before.
Thousands of alleged radical militants had been arrested in Bangladesh in recent weeks, local media reported.
By Nazrul Islam
