It looks like a military/police uniform on the three men in the photo. The tunic, belt and the one wearing breeches and puttees would seem to be in the same unit. That being said there is no rank, medals, unit markings or hats to narrow down exactly what type of uniform they're wearing. Do you have a general idea where he was in this photograph? It looks mediteranean, possibly Italian or Albanian? It's not a british/german/french uniform. So you'd have to check one of the other countries military/police uniforms.