Bridge Collapse in Minneapolis

I saw today's news on Yahoo home page , a bridge collapse in Minneapolis...Oh..no...it is so bad. I saw the picture and cars in the river...

How can it be like that ? This is in United States....I think my country usually have this accident but I don't think at United States it is same.

By the way I hope there are a little people get injured or died....I believe the people will get the best help in this time.They said that 30 people are stilll missing...