The 6th World Festival of Youth and Students took place in Moscow in 1957, permitting jazz and western forms of dance for one of the first times in the Soviet Union. Although there was some hope that this was an indication of relaxation of restrictions, by the end of the 1950s, Eastern Bloc countries began arresting stilyagi and rock fans. In 1958, partially in response to these events, NATO published a report speculating on the intentional use of rock music for subversive purposes.