The attack in Karachi caused further embarrassment after Osama bin laden was killed in Abbottabad [Reuters]
The head of NATO has admitted that the security of Pakistan's nuclear weapons is a matter of concern, the day after the worst assault on a Pakistani military base in two years.
Anders Fogh Rasmussen was speaking in Afghanistan on Tuesday, where he met Hamid Karzai, the Afghan president, to discuss the transition of security from NATO-led troops to Afghan security forces, which is due to begin in July.
"Based on the information and intelligence we have, I feel confident that Pakistan's nuclear arsenal is safe and well protected,'' Rasmussen said. "But of course, it is a matter of concern and we follow the situation closely."
Pakistani forces battled Taliban fighters for 17 hours before reclaiming control of a naval base in Karachi on Monday.
The attack, the worst on a base since the army headquarters was besieged in October 2009, piled further embarrassment on Pakistan three weeks after al-Qaeda leader Osama bin Laden was found living in the city of Abbottabad, close to the country's military academy.
The Pakistani Taliban said they staged the raid to avenge the May 2 killing of bin Laden. The fighters destroyed two US-supplied surveillance aircraft and killed 10 people on the base.
Police on Tuesday released an account of the Taliban assault, saying there were twice as many attackers as the number claimed by the government and navy, adding to the questions surrounding the deadly incident.
Government and naval officials said that six assailants had taken part in the assault, and that four had been killed and two had fled.
But a police report on Tuesday said that between 10 to 12 attackers were involved.
Shahrukh Khan, a local police chief, said the report was written after consultation with a navy officer.
Such a report is a formal part of opening an investigation into the attack. A navy spokesman said he was looking into the discrepancy.
Many analysts were surprised that just six attackers could occupy part of the base for such a long time against a force of hundreds of commandos and navy marines.
Pakistan security agencies are known sometimes not to give full accounts of violent incidents, and often hold suspects for months without informing the public.
The fact that the attackers managed to infiltrate so deep into the high-security base led to speculation they may have had inside information or assistance.