Does the Lord kill children?

I believe that before Jesus, people believed in a God who murdered children in one moment and a God of great mercy in the next moment. Jesus showed us the true nature of God as a loving Father and a God who forgave the sins of the world. Who is the God of the Torah? I also have read of a God of great mercy in the Torah and that God is called Yah. Are both personalities of God of the Old Testament the God Jesus calls Aba Father? What kind of God would send two she-bears to slaughter children for laughing at a bald man? The God I know and pray to is full of love and forgivenes but who is the God in the following scriptures? What do you think? This scripture has always insulted my sense of right & wrong. I would like to know what Christins and non-Christians would say about the following scripture;

2 Kings, 2:23-24.

23: And he (Elisha) went up from thence unto Bethel: and as he was going up by the way, there came forth little children out of the city, and mocked him, and said unto him, Go up, thou bald head; go up, thou bald head.
24: And he turned back, and looked on them, and cursed them in the name of the Lord. And there came forth two she bears out of the wood, and tare forty and two children of them."