Dhaka - A group of as many as nine gunmen attacked a restaurant popular with foreigners in a diplomatic zone of the Bangladeshi capital on Friday night, taking hostages and exchanging gunfire with security forces, according to a restaurant staff member and local media reports.Sumon Reza, a kitchen staffer who escaped the attack at the Holey Artisan Bakery in Dhaka's Gulshan area, told reporters that the attackers were armed with firearms and bombs as they entered the restaurant around 21:20 on Friday and took customers and staffers hostage at gunpoint.Jamuna Television, quoting Reza, said the attackers chanted "Allahu Akbar" (God is Great) as they launched the attack.Local TV stations reported that the attackers' identities were not immediately known.A huge contingent of security guards cordoned off the area around the restaurant, trading gunfire with the attackers who set off bombs and exchanged gunfire with the security officials.Benazir Ahmed, director general of the elite anti-crime force Rapid Action Battalion or RAB, told reporters at 11:20 p.m. (Dhaka time) that security forces were working to save the lives of the people trapped inside. Several foreigners are believed to be among the hostages inside the restaurant."Some derailed youths have entered the restaurant and launched the attack. We have talked to some of the people who fled the restaurant after the attack. We want to resolve this peacefully. We are trying to talk to the attackers, we want to listen to them about what they want," Ahmed said."Some of our people have been injured. Our first priority is to save the lives of the people trapped inside.," he said.He would not say how many people were trapped inside.In Washington, State Department spokesperson John Kirby told reporters: "We are aware of reports of what appears to a hostage situation in the Gulshan neighbourhood of Dhaka."He said the department is aware that local security forces are on the scene, responding, and the US Embassy is in constant touch with Bangladeshi authorities concerning what is a "very fluid, very live situation".Kirby said the embassy has accounted for all of American citizens that are under the authority of the diplomatic chief of mission in Dhaka. He said he had no more details.He said it was too early to say who was involved in the assault and their motivation.