Image copyright AP Image caption The attack targeted government and military workers waiting for their salaries

At least 33 people have been killed and 100 injured in a suicide bomb attack in the eastern Afghan city of Jalalabad.

The blast happened outside a bank where government staff and military personnel were collecting their salaries.

A spokesman for a group claiming to represent Islamic State in Afghanistan said it carried out the attack, though the BBC cannot verify the claim.

The BBC's Shahzeb Jillani in Kabul says it is the largest attack in Jalalabad in many months.

Children are said to be among the victims.

President Ashraf Ghani called it a "cowardly and heinous terrorist act".

On a visit to north-eastern Badakhshan province, he said: "Who claimed responsibility for the horrific attack in Nangarhar [province] today? The Taliban did not claim responsibility for the attack. Daesh [IS] claimed responsibility."

One eyewitness, Jaweed Khan, said: "I saw many people, dead bodies and injured people on the ground.

"Ambulances arrived very late, and many people died of their wounds."

Police said another bomb was discovered nearby, and was destroyed in a controlled explosion.

Another blast was also reported outside a shrine in Jalalabad on Saturday morning. There were no reported casualties.

Image copyright AP Image caption Police say the bomber attacked the bank on a motorcycle

Image copyright EPA Image caption A spokesman claiming to represent Islamic State said it carried out the attack on the New Kabul Bank

Shahidullah Shahid, who claims to be a spokesman for Islamic State (IS) in Afghanistan, said the group was behind the attack on the bank.

He also named a man who he said was the attacker. The BBC cannot confirm either claim. If confirmed, it would be Islamic State's first major attack in Afghanistan.

Mr Shahid was a spokesman for the Pakistani Taliban until he was fired for pledging allegiance to IS last year.

A spokesman for the Taliban, Zabihullah Mujahid, told news agencies the group was not behind the bank blast.

"It was an evil act. We strongly condemn it," he told Reuters.

Image copyright EPA Image caption Shahidullah Shahid (centre) said IS was responsible for the attack

Image copyright AFP/Getty Images Image caption Three people died in an attack on a Nato convoy in Jalalabad on April 10

Jalalabad has been a repeated target for the Taliban in the past year.

After years of Nato intervention, the challenge of fighting extremist groups is now solely in the hands of Afghan forces, but a new report indicates the number of troops and police is falling and creating new security risks.

Only a few thousand Nato troops remain in the country, largely in training roles, after their combat role ended in December.