Cat Problems with going to the bathroom?

Do you know what could be going on with my cat(s) and how I can fix this problem? I have had 3 cats (two boys one girl) for years now and a few months ago we brought a new cat (girl) into our home and nothing happened with my cats. A few weeks ago we rescued another new cat (boy) who had been abandoned. Now, weeks later, my family got home from a weekend camping trip and my cat(m) who is usually very social is hiding and my bed room is full of cat feces and urine, all over the floor, but the litterbox was clean and they've always used it before, what's going on? Thanks~ Sarah