The number of Securitate and Militia forces at Petroșani was doubled and military units were placed near all mines in the Jiu Valley. Securitate agents were hired as miners, not only to inform on other workers, but also to exert psychological pressures on them and even beat them before witnesses so as to create a climate of intimidation. A relatively large number of common criminals released from prison were brought into the mines as well. The Valley was declared a restricted area from 4 August until 1 January 1978. Strict surveillance was intended to block the flow of any information to the rest of the country or contact with the outside world, yet 22 miners acting on behalf of 800 others managed to send a letter (dated 18 September) to the French newspaper "Libération", which published it on 12 October. Foreign media drew a link between Paul Goma's movement that spring and the miners' unrest several months later, though no connection actually existed.