Excellent picture, thanks for posting it.
But I don't believe the picture was taken in the war, the ship doesn't carry neutrality markings.
The "Boka" was built in 1920 by Canadian Vickers Ltd., Montreal, as Canadian "Canadian Planter". 1936 sold to Yugoslavija as "Boka". 1939 or 1940 she transferred to the Panamian register without change of name, new owner Cia. Centroamericana de Nav.
20./21.09.40 torpedoed and sunk in convoi OB.216 by German submarine "U 138" en voyage Barry - Sierra Leone