Yes, agony to see others, esp. children, suffering in such a disaster.
But think for a moment that God HAS taken the children who have died from their homes, and taken them to a safer place with Him. How can He call us to Him, except through death? If we had enough faith, we would understand that death is a good thing, and not rail against any "unfairness" of it. Yet, we should still lament our lost loved ones, while waiting and suffering here in life until our turn to join them in peace and freedom from suffering.
Of those left to suffer through this terrible thing...how can we think that today is the end of God's working in their lives? It is a beginning, or a milestone. It is for some a day that their eyes are opened to the existence of God because they survived when others did not...or their eyes are opened to the existence of God because their only solace is to think that a dearly beloved one is now safe in the care and comfort of God. God will lead each one, comfort each one, strengthen each one-- if they let Him--and even if they don't, He will find a way.
Things like the tsunami, tornadoes, fires, etc., are sometimes the only way He can get our attention and remind us that it is not the THINGS in our lives that are important, but our relationships with Him and with others. When we have too many material possessions, we begin to think that WE are the source of our sufficiency, not Him.
This I speak not from a life of having been raised with a belief in God, nor of having been taught by other people much. I speak as one whose life was turned upside down by God working directly through His people to destroy my old life and lead me to a new one. It is a slow, painful process but I am very grateful for the pain and suffering, for they are the source of a faith and security that is unshakeable by the whims of the world, either the human world or the natural world.
So my prayer is that all may be comforted in their affliction, and know that the ultimate source of their comfort is a loving God who can use even the most horrible circumstances to bring us to Him, so He can better teach and sustain us.