7 Dead in attack on UN in Kabul; Taliban "This is our first attack."

KABUL (AP) -- Gunmen with automatic weapons and suicide vests stormed a guest house used by U.N. staff in the heart of the Afghan capital early Wednesday, killing at least seven people including three U.N. staff, officials said. A Taliban spokesman claimed responsibility, saying it was meant as an assault on the upcoming presidential election.

Heavy gunfire reverberated through the streets shortly after dawn and a large plume of smoke rose over the city following the attack on the hostel in the Shar-e-Naw district. Kabul police chief Abdul Rahman Rahman said seven people were killed, including some attackers.

U.N. spokesman Adrian Edwards confirmed that three U.N. staff were among the dead and one was seriously wounded. He said 20 U.N. staff were living at the guest house, some of them known to be registered there but he was unsure whether all were there at the time of the attack.

Flames could be seen on the roof of the guest house. Hours after the attack began, three explosions could be heard but it was unclear if they were from that location.

Following the attack, a rocket slammed into the grounds of the luxury Serena Hotel, which is favored by many foreigners. The device failed to explode but filled the lobby with smoke, forcing guests and employees to flee to the basement, according to an Afghan witness who asked that his name not be used for security reasons.

The guesthouse attack was the third major one in the capital in recent weeks.

On Oct. 8, a suicide car bomber detonated his vehicle outside the Indian Embassy, killing 17 people - mostly civilians - and wounding at least 76 more. The Afghan Foreign Ministry hinted at Pakistani involvement - a charge Pakistan denied.

On Sept. 17, a suicide car bomber killed six Italian soldiers and 10 Afghan civilians on one of Kabul's main roadways.

Taliban spokesman Zabiullah Mujahid claimed responsibility for Wednesday's attack in a telephone call to The Associated Press, saying three militants with suicide vests, grenades and machine guns carried out the assault.

He said three days ago the Taliban issued a statement threatening anyone working on the Nov. 7 runoff election between President Hamid Karzai and Abdullah Abdullah.

"This is our first attack," he said.

Afghans vote Nov. 7 in a second round election after U.N.-backed auditors threw out nearly a third of Karzai's votes from the Aug. 20 ballot, determining widespread fraud. That pushed Karzai's totals below the 50 percent threshold needed for a first round victory in the 36-candidate field.

The Taliban warned Afghans to stay away from the polls or risk attacks. Dozens of people were killed in Taliban attacks during the August balloting, helping drive down turnout.