Afghan officials say at least five people have been killed in what they said was a motorcycle suicide bomb attack.
A spokesman for the governor of eastern Nangarhar Province said eight people were wounded in the attack on December 3 outside a soccer stadium in the provincial capital of Jalalabad.
Attahullah Khogyani said the explosion occurred after a pro-government rally at the stadium, which had been packed with supporters of the government.
No one immediately claimed responsibility for the attack.
On December 2, two intelligence service members, including the director of the Jalalabad intelligence unit, were killed in multiple bomb attacks by alleged Islamic States militants in Jalalabad.
Ten people, including soldiers and civilians, were injured in the back-to-back explosions near a private radio and TV station.
A local affiliate of the Islamic State extremist group is seeking to expand its influence in Afghanistan.