Rats in the compost bin - help!

We use a metal trash can turned upside down to compost our food scraps. There are slits in the top and bricks hold down the lid. Once the food scraps are mostly decomposed, we transfer them to a large, open bin where we also compost weeds and leaves. Until now, the system has worked well.

It seems, however, for the first time in decades, rats have discovered our compost trash can! They are getting in through the bottom (probably digging) and eating the food scraps. We're pretty sure they are pooping in there, too - it's somewhat difficult to tell given that everything is frozen. The food scraps are definitely disappearing...

Does anyone know could we get rid of the rats without using poison?
And, if there is indeed rat poop in mixed in with the compost, is the compost safe to use?

Any tips would be greatly appreciated!

Peckhaus, I had rodents in my compost bins last winter too--they tunneled in and ate my Bokashi'd food scraps. I'd heard that rodents hate the scent of peppermint so I purchased some anti-rodent peppermint oil -sachets that I found at the garden store and put them into my bins. They were non-toxic so I felt safe doing this. Seemed to work for me.

As far as the question of rat-droppings in compost: I found a thread on this subject from a google search which turned up a Royal Horticultural Society garden-site (see below). Apparently, there isn't much danger, if any. Rodents, gardens, and compost-piles have been coexisting for quite a while.
http://mygarden.rhs.org.uk/forums/p/25346/52510.aspx

Peckhaus, I also found this non-toxic product listed at Park Seed on-line. Don't have experience with it myself.

http://www.parkseed.com/gardening/PD/6994

I have a nce vole tunnel going under my bin. I wouldn't worry about rodent poop in the compost germ wise, but of course you don't want to be having rats multiply. Or overrunning the garden when your nice produce starts growing. You can try snap traps the old type or the newer plastic ones, or sticky boards. Bait the trap area and withhold fresh stuff in the bin. Or the peppermint, or other repellant.

Fabulous! I will try the peppermint first since we already have something like that which we spray for deer. If it doesn't work, I'll move on to the other suggestions.

Thank you so much.

Peckhaus, let us know how what works for you!