Sixty-eight people were killed when a suicide bomber attacked a crowd of people protesting in eastern Afghanistan on Tuesday.
Provincial sources announced a significant increase in the death toll on Wednesday, confirming that the blast injured 165 people.
The bombing happened when a group from the district of Achin came to Momandara district to block the main highway between the capital Jalalabad and the Torkham border with Pakistan.
The Taliban denied involvement and no other group claimed responsibility.
A local affiliate of ISIS has emerged in recent years and carried out brazen and increasingly deadly attacks, most often targeting civilians and the country's minority Shiite Muslims, who it views as apostates. The Taliban and the ISIS affiliate are enemies and have attacked each other's forces.
Tuesday's attack was marked by one of the highest death tolls in attacks in Afghanistan this year. In January, a Taliban-claimed suicide bombing in the capital Kabul killed at least 103.
Afghan president Ashraf Ghani strongly condemned the suicide attack against the demonstrators in Nangarhar. In a statement, he said "attacks on civilian facilities, mosques, women, children, are all crimes against humanity."
Tuesday's attack came on the same day a double suicide bombing hit a school in Jalalabad. One boy was killed and four others wounded.
Nangarhar has been one of the most volatile regions in Afghanistan this year, the scene of many suicide bombings. The province has been an ISIS stronghold since early 2015.
In western Herat province, Taliban insurgents attacked a police checkpoint, killing six police, said Abdul Ahad Walizada, spokesman for the provincial police chief.
Mr Walizada said another officer was wounded in the Tuesday night attack in Pashtun Zargun district. He added that 10 insurgents were killed and six others wounded during a gun battle with a reinforcement unit.
The Taliban have not commented on the attack but Mr Walizada said Taliban are active in the district and often target security checkpoints.
It has been a bloody summer for Afghanistan, with co-ordinated attacks on cities, bombs on soft targets like schools and assaults on buildings that have killed hundreds of civilians and members of the security forces.
Hopes for peace between the Afghan National Army, which is supported by a United States-led Nato coalition, and the Taliban rose recently, putting an end to the 17-year conflict within sight.
The Taliban, however, refuse to negotiate with the Afghan government, which they see as illegitimate, preferring to speak only to the US.