Gul Agha Shirzay said suicide attackers armed with guns and grenades carried out the attack.

The Taliban say they carried out the assault on the Kabul Bank, targeting police and intelligence officers who had gone to collect their salaries.

Afghan security forces are frequently targets of attacks by the Taliban.

"Unfortunately 18 of our countrymen were martyred and more than 70 injured," said Mr Shirzay, governor of Nangarhar province.

Those wounded included Alishah Paktyamwal, the province's police chief, and his deputy.

Afghan President Hamid Karzai condemned the attack.

"People were there doing business deals and to receive their salaries. This attack once again showed the cruel actions of the terrorists who do not want the people of Afghanistan to live in peace," he said.