Four guards were killed when a suicide bomber blew up his car outside a small residential hotel used by foreigners in northern Afghanistan early today.
At the same time, two other militants stormed the hotel in Kunduz city and engaged Afghan police officers in a two-hour gun battle.
The Taliban claimed responsibility for the assault - the latest in a rising number of attacks in the area.
The blast rocked the neighbourhood all around the building in Kunduz city, said provincial spokesman Mubobullah Sayedi.
"When the bomber blew himself up, the explosion shook everything," he said. "It broke glass everywhere."
Four Afghan building guards were killed and 10 other people, including an Afghan policeman, were wounded, Mr Sayedi said. Foreigners staying at the two-storey hotel escaped through the rear of the building, he added.
Sarwar Husseini, a provincial police spokesman, said German aid workers often stayed in the house, but it was not clear who was staying there when the attack took place.
The Interior Ministry said the house was used by GIZ, a German development and assistance organisation which contracts mostly with the German government.
Taliban spokesman Zabiullah Mujahid said in a text message to The Associated Press that the assailants had attacked a "German intelligence centre and security company".
The inn burned and several nearby buildings were damaged. Flames could be seen shooting up an exterior wall as police contained the area.
"We heard a very big explosion that shook all of Kunduz," said a 30-year-old shopkeeper, who lives about 10 yards from the building. "It was a very strong explosion."
Ahmadullah, who uses just one name, said he and his family quickly ran out of the neighbourhood to a relative's house nearby. Worried that they were still too close to the fighting, they moved even further away to seek protection in another relative's house.
"All my children were so scared," he said. "We have never been so close to a suicide bombing."
Fighting has been focused on southern and eastern Afghanistan, but insurgents have been conducting a rising number of attacks in the once-peaceful north.
Late last month, a vehicle carrying the deputy governor of Kunduz province struck a roadside bomb, injuring three of his bodyguards.
In June, a bombing at a bazaar in the province killed at least 10 people.
Also in June, three policemen were killed when a suicide bomber blew himself outside a mosque and another bomber hit a German Nato convoy, killing three civilians.
In May, a suicide bomber infiltrated a high-level meeting in neighbouring Takhar province and killed northern Afghanistan's top police commander, General Mohammed Daoud, provincial police chief Shah Jehan Noori and two German soldiers. The German Nato commander in northern Afghanistan was wounded.
Late last year, a suicide bomber killed Kunduz Governor Mohammed Omar and 15 other people at a mosque in neighbouring Takhar province.Reuse content