Light leaks or lens flare?

[JordanF]

Hi all,

I'm new to LF and have just developed my first batch of shots with some success.

However one of the images was ruined by a white streak through it that I suspect is either a light leak or lens flare and could use an opinion on differentiating the two.

The camera is a new Chamonix 45N-2, and I havent had the problem on any other images (though this is the first time I have used this particular holder). I would have thought that a light leak would start at an edge where as this doesnt seem to. Does it look like lens flare?

Much appreciated