Mr Boulierac also stressed that other children "are wounded and are now fighting for their lives," which means that the toll among minors from the Sunday attacks could rise, the AFP says.
Meanwhile, the BBC has reported citing Lankan police that the death toll from the attacks has risen to 321 with about 500 wounded.
Sri Lanka's government has blamed the blasts on local Islamist group National Thowheed Jamath (NTJ), though none of the extremist organisations has claimed responsibility for the attacks so far.
Colombo has launched a massive security operation in the wake of the tragedy. As of Monday, at least 24 people were detained in connection with the attacks.