Could even be Romanian if one saw any hint of blue in the first vertical bar of the flag instead of black.
you hit either a Belgian or a Romanian
but its definitely not french as the center bar is yellow
EDIT
It IS romanian... i just isolated the first color in the flag and it is a near navy blue... not black.
I commend you for going to so much trouble to verify the nationality before attacking.
but i believe any board of inquiry would clear you of any wrong doing. The ship was darkened in a combat zone, and you did your due diligence in identifying the nationality of the craft.
such is war
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