Over the 1950s, the service became more professional and better coordinated with civilian authorities. Many noteworthy civilian volunteer mountain rescue teams in the UK began as RAFMRS "sub-units." Two air crashes high in the mountains of Turkey during the 1950s provided call-outs for the first of several overseas teams of the RAFMRS, based at RAF Nicosia in Cyprus. Both crashes had a sense of Cold War espionage, involving secret nuclear papers and equipment. To this day the service's historians feel they lack all the details. Other overseas teams were based in Aden, Sharjah, Sultanate of Oman and Hong Kong. The middle eastern teams were characterized as "desert rescue," and British Army personnel were occasionally involved.