Taliban insurgents claimed responsibility for the assault, one of the boldest on the capital since U.S.-backed Afghan forces removed the group from power in 2001. The Taliban said their main targets were the German and British embassies and the headquarters of Afghanistan's NATO-led force. Attackers fired a rocket-propelled grenade that landed just outside the front gate of a house used by British diplomats in the city centre and smoke billowed from the area after the blast, a Reuters witness said. British embassy sources said staff were in a lockdown. A spokesman for NATO's International Security Assistance Force (ISAF) said via Twitter that there were no reports of casualties on possibly seven locations in Kabul. "ANSF and ISAF responding as needed," the spokesman said, referring to Afghan security forces and their NATO partners. However, fighting was going on near the U.S., Russian and German embassies, and at some ISAF facilities, the Twitter report said. Three other rockets hit a supermarket near the German Embassy popular with foreigners, Reuters witnesses said. Shooting came from various directions in an area close to both the U.S. and British embassies, while smoke billowed from the nearby German embassy, the Reuters witnesses said. Attackers also fired rockets at the parliament building in the west of the city, and at the Russian embassy, a spokesman for the parliament said. Most MPs had left the building before it came under attack, said a lawmaker. In the eastern province of Paktia, insurgents occupied a four-storey building near the compound of the chief of police, a witness said. A helicopter gunship from Afghanistan's NATO-led force was firing at the building in the province on the Pakistani border, which has been plagued by violence for years. Reporting by Amie Ferris-Rotman, Rob Taylor and Jack Kimball; Writing by Robert Birsel and Michael Georgy; Editing by Raju Gopalakrishnan