KABUL - SIX foreigners have been killed and another five wounded in an attack on a Kabul guesthouse used by staff of the United Nations, an Afghan official said on Wednesday.

'Three suicide bombers have been killed during the police operation, they were armed suicide bombers,' said Zemarai Bashary, spokesman for the interior ministry. 'Unfortunately six foreigners have been killed, five foreigners have been wounded,' he told AFP.

Gunfire and explosions rang out across the city in a smart residential district near the famous Chicken Street shopping thoroughfare favoured by Westerners.

The attack came with tensions rising in Afghanistan ahead of the scheduled presidential second-round election on November 7, and after a string of high-profile suicide attacks in recent months.

Police and other Afghan officials said at least one of the attackers was killed, possibly after detonating an explosives-packed vest, and several police officers were wounded.

Afghan police were locked in a stand-off with a 'group of terrorists' holed up in an apartment building, one police officer at the scene said. -- AFP