Did a search and no recent threads..... We bought the TT late last fall. Didn't really spend much time putting her away properly. I'm guessing the powercord is most likely where they got in, but ...
The problem with the "green blocks" is that any thing that eats the mouse after it eats the block gets poisoned too. I don't believe in poisons when there are so many other methods that are safer. But, That is my opinion.