Overheard a conversation of somone who sounded like they were on the run, should I report it ?

So on the bus last night I overheard a phone call of somone seemingly on the run/hiding. (Idk if it was from the police, or another person) They were discussing going to another city, changing the clothes and the airport/coach at one point too.

Usually I would dismiss this. But it was a young kid (11-14) and it was pretty late at the time.

The issue is I don't know their name or how they look, just they were dressed in black. Furthermore I couldn't seem to find them on missing/wanted lists in my region.

I would go to the local station and talk yo them about it but there isn't a local station. And I feel like I know way to little to be worth making an official report or call.

Should I leave it, or call 101, or do somthing else ?