The doctor in Aybak, about 200 kilometers (130 miles) north of the capital Kabul, said the casualties were mostly youngsters.
"All of them are children and ordinary people," he told AFP, asking not to be named.
A provincial official confirmed the blast, but could not provide casualty figures.
Earlier on Wednesday, another blast rocked western Pakistan, killing at least 3 people and wounding another 23. Local branch of Taliban took responsibility for the suicide bombing attack.
There have been dozens of blasts and attacks targeting civilians since the Taliban returned to power in August last year, most claimed by the local chapter of the Daesh (ISIL or ISIS) terrorist group.
The Taliban says it is focused on securing the war-torn nation since taking over the country last year.
However, several attacks have taken place in recent months, some of which have been claimed by Daesh.
Source: i24news.tv