Escape Artist

A couple of weeks ago I went home for lunch to let the dogs out. When I opened the bedroom door Pete was there to greet me. I panicked.... We forgot to put him in his crate. Wrong... His crate door was locked. After close inspection he busted out the side. We have a wire crate that folds for travel. We have heard of dogs doing this but Pete loves his crate or he did until we moved in with parents. I have been worried this would happen again. And it did yesterday. When Chad got home he put Pete in his crate, set up his i-phone to video Pete, and left the room. After standing outside for awhile Chad returned and watched the video. Pete is scratching and biting his way out. Does anyone else have this problem? I guess we will have to wire it shut.