What are these marks on brickwork?

[David-mbtml]

Hi all, as above really - I assume these White marks on the brickwork are a water leak but I can't see how based on the overhang of the roof. Anyways how would I go about cleaning them off and would I be able to get rid of it completely?

[David-mbtml]

Awesome thanks all. In the process or buying the house and should be moving in towards the next 3-4 weeks. Obviously hadn't had the chance to observe it yet so will have a better look when I move in and go from there. No signs of damp inside at all, all externally cosmetic so would like to fix it just to look better really