I got the "FBI" ransomware virus last Fall, then in January picked up the "Homeland Security" ransomware virus -- actually it's the same virus with different screens to lock up your computer. If you get it, DO NOT pay the ransom. That won't get rid of it. I was able to get rid of it myself by following the instructions on the web. Just be sure to have a bootable disk available as you can't always get into Safe Mode when infected.
Just do a search for "FBI ransom virus" and get the instructions. It helps to have another computer available if you don't print out the instructions ahead of time. It's a nasty one for sure.