The gunmen targeted the van of a private school in Mattani area this afternoon.
Five children were killed instantly, police officials were quoted as saying by TV news channels.
The condition of two of the five injured children was described by officials as serious.
The gunmen struck as the van was taking the children back to their homes.
No group has claimed responsibility for the ghastly attack.
Security forces launched a search operation to trace the attackers.
A suicide attack was carried out on a security check post in the same area nearly two years ago.
Published 13 September 2011, 08:15 IST