Afghan Taliban assault in Kabul secure zone
Afghan security forces have put down a militant gun and bomb attack near the presidential palace, in one of the most secure areas of Kabul.
Officials say four insurgents and three security guards died. The Taliban say they carried out the attack.
President Hamid Karzai was in the palace, but the target appears to have been the nearby Ariana hotel, which houses a CIA station.
This is the latest in a string of attacks on Kabul in recent months.
Most recently a suicide bomber in the capital targeted a prominent Afghan politician on 18 June, just hours before Nato formally handed security responsibility to the Afghan forces.
With this attack the Taliban infiltrated one of the most heavily-guarded areas of the capital, with several key buildings such as the defence ministry and Nato headquarters located very close by.
The Afghan Taliban have showed no sign of abating their assault on security targets, despite last week's announcement that they had set up an office in the Gulf state of Qatar for peace talks.
In another attack on Tuesday, at least 10 civilians, including eight woman were killed when a roadside bomb hit their vehicle in Afghanistan's southern Kandahar province.
President Karzai raised strong objections to the Taliban office, saying the flag and nameplate initially erected at the building showed they were trying to portray themselves as a government-in-exile.
Officials say the High Peace Council, the Afghan government body set up to lead peace efforts, would not take part unless the talks process was "Afghan-led".
The attack near the presidential palace, in the central district of Shash Darak, began at about 06:30 local time (02:00 GMT).
The militants initially targeted the palace's eastern gate - a few hundred metres from the actual building - where dozens of journalists had gathered for a news conference with Mr Karzai scheduled for 09:00.
The BBC's Bilal Sarwary, who was among the crowd of journalists, says they were forced to run for cover as bullets flew overhead.
The journalists heard several explosions, and reports said grenades were being thrown. Tolo TV reported as many as 14 blasts.
Our correspondent says the area around the palace, which is patrolled regularly throughout the day by special forces and intelligence agents, is now under lockdown.
Taliban spokesman Zabihullah Mujahid said in a text message: "A number of martyrs attacked the presidential palace, defence ministry and the Ariana Hotel."
The Ariana Hotel is known to house a CIA station.
Kabul's police chief, Ayub Salangi, said the attack was brought to an end just under two hours after the first shots were fired.
Four attackers wearing uniform and carrying fake ID cards began the attack, with one blowing himself up, a defence ministry spokesman told the BBC. They were eventually killed by private security forces attached to the hotel.
The Nato-led International Security Assistance Force, whose headquarters is also not far from the scene of the attack, wrote on Twitter that the Afghan National Security Forces had led "the response efforts".
Last week, Afghan forces assumed security responsibility for the whole of the country for the first time since the Taliban government was ousted in 2001.
International troops will remain in Afghanistan until the end of 2014, providing military back-up when needed.