DoS Attempts

Hello - I happened to be checking my logs and see several unsuccessful attempts every day or every other day starting on 7/10 by the same 3 IP addresses attempting to get into my PC. The intrusion detection states that “The source IP address has apparently attempted a Denial of Service against your computer by sending a large amount of invalid fragmented packets.” I’ve since banned all 3 IP addresses. I’ve had limited success in tracing the addresses but am fairly certain I know who is behind the attempts. Any ideas on how to catch or other advice?

if it the same address over and over, you can report it by following the advice here http://www.justice.gov/criminal/cybercrime/reporting.htm