Afghan gunfight: Kabul police battle insurgents
Afghan and international security forces have been battling a multi-pronged attack by insurgents targeting the US embassy, Nato headquarters and police buildings in Kabul.
Police are still exchanging fire with at least one gunman holed up in an unfinished high-rise building overlooking the diplomatic quarter.
Six people have been killed and 16 injured, Kabul's police chief said.
The Taliban said they were behind the violence.
At least one attacker remains on one of the upper floors of the building, says the BBC's Quentin Sommerville, in Kabul.
Afghan intelligence officials are already going through the lower floors, gathering evidence about the way the attack was planned and carried out.
Two of them told the BBC they found rocket-propelled grenades (RPGs), heavy machine guns and hand grenades, as well as biscuits and energy drinks.
"They had planned a long battle," one official said.
Counter-terrorism officials said they recovered three mobile phone Sim cards from the bodies of attackers killed earlier in the day. The records showed the numbers had been used for calls to and from Pakistan, they told the BBC.
The insurgents were wearing burkas and travelling in a minivan, said Kabul's police chief.
"We don't have female police officers to search females," General Ayub admitted.
Nato and the US embassy said none of their staff were casualties of the attack. A US embassy spokeswoman said four Afghans were hurt, but none of them had life-threatening injuries.
"We appreciate the response of the Afghan National Security Forces whose operations stopped the attack on the embassy compound," the embassy said in a statement.
Gen Ayub said the insurgents wanted to carry out attacks in Kabul to coincide with the 10th anniversary of 9/11. Although the Taliban said they carried out the attack, Gen Ayub put the blame on the Haqqani network, an insurgent group linked to the Taliban but which operates independently.
Afghan counter-terrorism sources told the BBC: ''We have seized three Sim cards from the dead attackers. Phone calls were made to and from Pakistan. Right now we are going through it.''
Nato said the attack was an attempt to derail the security handover to Afghan-led forces, as international troops begin to withdraw from Afghanistan.
Tuesday's attacks appear to be a complex operation. At about 13:30 local time (09:00 GMT), insurgents fired rockets on a number of targets in Kabul's upmarket embassy district.
In the west of the city, another two suicide attackers detonated explosives outside a police station.
A third was killed as he tried to make it into the airport. A jail run by the intelligence service was also a target.
At least six gunmen took over an unfinished high-rise building near the Abdul Haq roundabout, overlooking the embassy district, and used it to fire on the Nato compound and US embassy.
A Taliban spokesman said the group was carrying out "a massive suicide attack on local and foreign intelligence facilities".
US marines were seen on the roof of the embassy building assessing the situation and checking their defences were robust, correspondents say. Military helicopters, including Black Hawks, flew over the area.
Nato's Secretary General Anders Fogh Rasmussen condemned the violence, describing it as an attempt to test the handover of Afghanistan's security to Afghan-led forces, an effort that would not succeed.
"We have confidence in the Afghan authorities' ability to deal with this situation," said Mr Rasmussen in Brussels. "Transition is on track and it will continue."
A trader in the embassy district told the BBC his office was hit by an RPG.
"I saw my cook die and several other people injured. The rocket came like a bullet. I didn't even have time to move an inch," he told the BBC.
Another witness, a Briton who asked to be identified only as Mike, was working nearby at the time.
"About 13:10 local time [08:40 GMT] there were some... shots fired," he said. "You think, 'Okay, it's Kabul'.
"Five minutes later, there was more coming from slightly different directions. Gunfire got heavier: until I could get out, it was about three hours.
"At times, there were heavy machine guns."
Everyone in his office got out safely, he said.
One rocket hit a school bus but it was apparently empty at the time.
Another eyewitness, Himanshu Sharma, told the BBC: "I thought it would be over in a few minutes, but then one hour and then two hours and then three hours passed - it was just not stopping.
"The gunshots were increasing, and their intensity was increasing. They were using more deadly weapons."
He went on: "There is no security at all in Kabul. This is the safest area, and if we are not safe here, then we are not safe anywhere in Afghanistan. "
Iranian Press TV said its office in Kabul had been attacked and one person was injured.
As well as housing the US and other foreign missions, the area is home to a number of government ministry buildings and the presidential palace.
This year has seen the most bloodshed in Afghanistan since US-led forces toppled the Taliban in 2001.
The violence has intensified since July, when Nato began the long process of handing power over to Afghan forces. Most international troops are scheduled to leave by 2015, provided Afghan forces are ready to take over security.