- Police: The explosives were in a pillow placed near a school wall
- It wasn't immediately clear who was behind the blast or if it was intentional
The children were killed around 3 p.m. when the explosives -- in a pillow placed near a school wall -- went off as they were playing in Kandahar, said Ahmad Zia Durrani, a spokesman for police in southern Kandahar province.
The incident happened at a madrasa, or Islamic school, that has dormitories where students sleep.
It was not immediately clear who was behind the blast or if anyone intended for the explosives to go off near the schoolchildren.
Still, such bloodshed is all too common in Afghanistan.
The nation has seen sometimes sporadic, sometimes sustained violence for years. A U.S.-led invasion after the September 11, 2001, terrorist attacks helped push out the ruling Taliban, though it did not eliminate the group -- which has claimed credit for numerous attacks, including a suicide bombing on Tuesday aimed at international forces in Kabul