Police battle gunmen in Bangladeshi capital Dhaka
A gun battle is taking place between police and unidentified attackers in the diplomatic area of the Bangladeshi capital, Dhaka, officials say.
Three people, including two police officers, have been wounded after gunmen stormed a cafe in the Gulshan district, police say.
The Dhaka Tribune said at least 20 civilians had been taken hostage, but this was not confirmed.
Police and security forces have sealed off the area.
The US embassy in Dhaka tweeted that there were "reports of shooting and hostage situation".
"Unknown number of people are still inside but we cannot confirm whether they are held hostage," police officer Sayedur Rahman told AFP news agency.
Local media reported that several gunmen had entered the Holey Artisan Bakery cafe and opened fire.
The cafe is described as being popular with expatriates, diplomats and middle-class families.
It is not clear who the attackers are, although a police officer told the BBC that Islamic militants were suspected.
BBC South Asia editor Jill McGivering says that although high-profile gun attacks are rare in Bangladesh, the latest incident follows a series of murders widely blamed on Islamist extremists.
BBC
Local media report that a group of up to nine attackers took hostages inside a restaurant frequented by both locals and foreigners in a diplomatic zone in Bangladesh's capital.
Bangladesh TV stations reported that the attackers entered the Holey Artisan Bakery in Dhaka's Gulshan area around 9:20 p.m. Friday and were holding customers and staff hostage.
The TV reports said the identities of the attackers were not immediately known.
The reports say a huge contingent of security guards cordoned off the area and the restaurant as they traded gunfire with the attackers who set off explosions.
Jamuna Television reported, quoting a kitchen staff worker at the restaurant who escaped the attack, said that the gunmen chanted "Allahu Akbar" (God Is Great) as they launched the attack.
USA TODAY reports
Gunmen take at least 20 foreign hostages in Bangladesh diplomatic zone
Gunmen took at least 20 foreigners hostages Friday at a restaurant in the upscale diplomatic zone of Dhaka, the capital of Bangladesh , according to local media.
The U.S. State Department reported a "hostage situation" at the location. In Washingotn, State Department spokesman John Kirby said there was "100 percent accountability" of all Americans working at the embassy, but could not declare they were out of harm's way.
According to the Dhaka Tribune, three people were shot during the takeover, including two policemen, who were shot in the leg.
The newspaper quoted Sumon Reza, a supervisor at a bakery adjoining the restaurant, as saying at least 20 people, all foreigners, were taken hostage by at least two gunmen armed with small firearms and a sharp weapon.
He said the gunmen, described as being under 30, shouted "allahu Akbar (God is great)" when they entered the O'Kitchen restaurant.
Gulshan police station duty officer Sayedur Rahman tells CNN that an unknown number of people are "trapped" at a restaurant.
