Twenty hours after gunfire and explosions rocked Kabul Tuesday, government security forces declared the standoff officially over as the last of the Taliban insurgents was killed, according to authorities.

Afghan Interior Ministry spokesman Sediq Sediqqi went to Twitter in announcing on Wednesday that all of the attackers who launched the well-coordinated assault on central Kabul, were dead.

"The operation just ended and six terrorists were killed by police. Details on casualties will be announced later," the official tweeted and as reported by Reuters.

Media reports have indicated that the Taliban had intended to rattle the capital's centre of diplomatic and military activities, where foreign missions from countries supporting the NATO-backed campaign were mostly located.

It was unclear at this time if the attack caused casualties among the coalition troops, in which Australia maintains a number of military personnel, but initial reports provided by the authorities pointed to nine deaths, mostly of Afghan police officials and civilians, and 23 injured.

A related attack on a nearby U.S. military installation reportedly resulted to the wounding of more than 70 U.S. service members but the numbers have yet to be confirmed by any American or NATO officials.

Observers said the attack marked the first time that both Afghan security forces and coalition troops were engaged by the Taliban in a drawn-out siege, which further questioned the ability of Afghan President Hamid Karzai to deal with the country's security as foreign troops start their planned drawdown later this year.

U.S. President Barack Obama had announced earlier this year that all American soldiers will be out of Afghanistan by 2014, indicating that other foreign troops, including that of the United Kingdom and Australia, will pull out much earlier.

Both nations though have recently stressed that they will abide with previously determined calendar of mission and campaign in the country and will only ship out once the NATO is officially completed.