did god create the tsunami?

If He did, was it the Christians God, or was it the Islamic's God?

Whichever it was, He was strong on the indiscriminate aspect of it all, targetting the most needy of the world's population.

Why did he do it? He's supposed to be merciful.

If He didn't do it, why did He allow it to happen?

Are there any of my religious brethren out there who would care to comment on these vexing questions, and whether there is a God at all, or just Mother nature and a lot of naive human beings?