Network Intrusions

Hi I recently looked at my Comodo firewall event logs and I noticed there were 28 network intrusions.

Application : System
Action: Blocked
Target: In
Protocol: UPD
Source port: 137
Destination port: 137

I looked up the source IP and Destination IP and they are both located in UK one says ministry of defense UK. I do not live in the UK so this doesn’t seem to be a local network?

I’m a complete noob when it comes to these sort of things and I just would like some input on weather or not these intrusions are dangerous I know it says it blocked them but what could be causing them in the first place? Any help is greatly appreciated.