At least 28 people have been killed and more than 300 wounded in a suicide bombing and gun attack in Kabul.
Civilians and members of the Afghan security forces were among those caught in the assault, which was claimed by the Taliban.
The bombing, during Tuesday morning’s rush hour, targeted the headquarters of a security agency in central Kabul, near the ministry of defence and embassies.
There were also reports of gunfire amid claims that Taliban militants had fought their way into the National Directorate of Security, Afghanistan’s main intelligence agency.
Afghanistan's health ministry said that casualty estimates are expected to rise as fighting continued.
A propaganda statement issued by the Taliban said the attack was part of its previously announced “spring offensive”.
It claimed a car bomb was detonated at the gates of the “10th directorate intelligence building” at 9am local time (5.30am BST) before gunmen rushed inside.
“Security forces are in a fight with an unknown number of armed insurgents right now,” Mohammad Afzel, a police officer at the site of the attack, said.
The area was closed off by security forces as fighting continued and dozens of ambulances were seen at the scene.
The health ministry said 327 injured victims, including women and children, had been taken to local hospitals.
A spokesperson at the presidential palace, just a few hundred metres from the blast, condemned the attack.
“Such cowardly terrorist attacks will not weaken the will and determination of Afghan security forces to fight against terrorism,” he added.
A tweet from President Ashraf Ghani said the assault “clearly shows the enemy’s defeat in face-to-face battle” with government forces.
The Taliban controls swathes of Afghanistan, where Isis is also trying to expand its presence amid deteriorating security.
Islamists have been gathering strength since the bulk of British, American and Nato forces withdrew in 2014, sparking an exodus by hundreds of thousands of refugees and pleas by local officials for help to combat insurgents.
Afghanistan’s defence minister, Masoom Stanikzai, warned last week that al-Qaeda is also gathering strength in the country and “preparing themselves for bigger attacks”.
Additional reporting by agencies
