Kabul, November 28: A huge explosion was heard in Kabul on Saturday, according to witnesses, but the immediate cause was not known.
The explosion happened around 10:20 am (0550 GMT) and was immediately followed by the sound of sirens as security forces rushed to the scene, apparently in central Kabul.
Afghanistan is marking the Eid-al-Adha Muslim festival of sacrifice with a four-day holiday.
No government or security officials could be immediately contacted for comment.
An international security company, Hart, sent a circular to clients to say the explosion had happened in the wealthy Wazir Akbar Khan neighbourhood of the city.
A report said an explosive device appeared to have been placed in a rubbish bin but that there did not seem to be any casualties.
Kabul, the most heavily-fortified part of war-torn Afghanistan, has been attacked by Taliban-linked insurgents at least five times in recent months with at least 100 people dead and 300 injured.
Most have been suicide car bomb attacks that the Taliban have claimed responsibility for.
On November 13, a suicide blast struck near a US military base, Camp Phoenix, though there were no deaths.
–Agencies