FAIZABAD, Afghanistan -- A motorcycle-riding suicide bomber attacked a bank branch Saturday in eastern Afghanistan, killing at least 33 people in a deadly attack the country's president said was claimed by the Islamic State group.
The attack marks a major escalation in the country's fight against an affiliate of the extremist group that now holds a third of Iraq and Syria in its self-declared caliphate.
It also comes as Afghan security forces fight against the Taliban after U.S. and NATO forces ended their combat mission in the country at the start of the year, yet another challenge for the war-ravaged nation.
The attack in Jalalabad, capital of eastern Nagarhar province, targeted a crowd of soldiers and civilians gathered outside the bank to receive their monthly salaries. The blast killed at least 33 people and wounded more than 100, said Dr. Hamayon Zaheer, the head of Jalalabad's hospital.
Hours after the attack, President Ashraf Ghani blamed the Islamic State group for the attack.
"In the horrific incident in Nangarhar, who took responsibility? The Taliban didn't claim responsibility. Daesh claimed responsibility for it," Ghani said, using an Arabic acronym for the group.
Ghani warned before that the Islamic State group was starting to establish a presence in Afghanistan. He used his visit to the United States last month to reiterate his concerns that the extremist group was making inroads into Afghanistan.
"If we don't stand on the same line united, these people are going to destroy us," he told the 600 people gathered at the provincial government headquarters in Faizabad.
He called on the Taliban to join with the Kabul government, and said that any Taliban who switched allegiance to Islamic State group would earn the wrath of Afghanistan's religious leaders.
Meanwhile, another bombing in the Behsud district of Nangarhar province killed one civilian and wounded two others, authorities said.
The Pakistani government, which is coordinating with Afghanistan on counter-terrorism issues, condemned the Saturday attacks.
A statement released by the Pakistani Foreign Ministry called the bombings cowardly and indiscriminate, and said attacks against civilians have no justification under any circumstances.
--Associated Press writer Zarar Khan in Islamabad contributed to this report.