In 1961, the "Grenzpolizei" were reorganized as the Border Troops of the GDR ("Grenztruppen der DDR") and were moved from the Ministry of the Interior, which oversaw policing, to the Ministry of National Defence (MfNV) which oversaw the military. The "Grenztruppen" became the fourth service branch of the National People's Army (NVA), the armed forces of the GDR. In 1973 they were separated and became directly subordinate to the MfNV, on grounds of not to be counted in MBFR. While wearing standard NVA uniforms, the "Grenztruppen" had their own dark green arm-of-service colour, and their service and dress uniforms bore a green cuff title with white lettering ""Grenztruppen der DDR"" on the left arm. The vast majority of "Grenztruppen" efforts were directed along the GDR's western borders with West Germany and West Berlin, with only about 600 members assigned to guard the GDR's borders with Poland and Czechoslovakia. This continued until the 1980s when the rise of the Solidarity trade union in Poland saw the GDR considerably toughen the "Grenztruppen"'s presence along their border.