Attahullah Khogyani, spokesman for the provincial governor, said 165 others were wounded in the attack a day earlier.
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 any involvement. No any other group immediately claimed responsibility, but both Taliban insurgents and the daesh(ISIS) are active in eastern Afghanistan, especially in Nangarhar province.
A local affiliate of the daesh(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 thedaesh(ISIS) are enemies and have attacked each other's forces.
Both the Taliban and IS carry out near-daily attacks in Afghanistan targeting security forces and government officials.
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 that "attacks on civilian facilities, mosques, women, children, are all crimes against humanity."