Sri Lankan hospital hit by mortar shells . Children young as 4 are treated in local hospitals for their injuries . Aid workers rescue 50 critically injured children and 2 adults . Sri Lankan President has promised to allow safe passage to trapped children .
Sri Lankan hospital hit by artillery shells . Children young as 4 months treated in local hospitals for shrapnel injuries . Aid workers rescue 50 critically injured children and 105 adults . Sri Lankan President has promised to allow safe passage to trapped civilians .