In the town Oklee, MN, a man was arrested after making a 911 call saying that his 3 month old wasn't breathing and was bleeding from her nose. They found significant bruising on her head, neck, and body. They also discovered sever damage to her genitals. The man admitted that he shook the baby a few times and tried fingering the child to get it to stop crying.
It seems to me that just shaking the baby wouldn't cause the amount of bruising they described and blood was found on babywipes in the diaper hamper.