Although Romania adhered to the Organization for Security and Co-operation in Europe (1973) and signed the 1975 Helsinki Final Act, Ceauşescu also intensified political repression in the country (beginning in 1971). This took a drastic turn in 1977, when, confronted with Paul Goma's movement in support for "Charter 77", the regime expelled him and others from the country. A more serious disobedience occurred in August of the same year, when Jiu Valley miners went on strike, briefly took hold of Premier Ilie Verdeţ, and, despite having reached an agreement with the government, were repressed and some of them expelled ("see Jiu Valley miners' strike of 1977"). A newly created and independent trade union, SLOMR, was crushed and its leaders arrested on various charges in 1979. Progressively during the period, the Securitate relied on involuntary commitment to psychiatric hospitals as a means to punish dissidence.