In 1918 the new Czechoslovak railways established its own security infrastructure, which at that time served only as a backup force for the regular police. Armed men protecting the railways were established in 1935, their functioning was regulated by the Law No. 86/1937 Zb from the year 1937, which also established the Armed guards units of the railways (). Later, in the 1950s, Public Security at the Railways () was created. Law No. 51/1964 Zb. established the Units of Armed and Fire protection of the Railways () in 1964. In 1967, under the OPOŽ units, an independent investigation service was established by Law No. 46/1967 Zb. After the fall of communism in 1989, federal power ceased over the protection of the railway system in 1992. Law No. 61/1993 Z. z from the year 1993 created a separate Slovak Railway Police by transforming part of the Federal Railway Police.