There was a period of ethnic tension in Cyprus, which commenced in 1963, and which had an impact on amateur radio in Cyprus.

DX News Sheet reported in September, 1964 "All 5B4 stations closed down last Thursday (5B4AHJ:1964-09-17) except those in British Crown Territory; the latter have reverted to the ZC4 prefix".

Below is a licence revocation letter from the Minister of Communication and Works to 5B4JF, who is now G3UCQ:

Related articles:

5B, MD7, ZC4 - Island of Cyprus, 5B4, ZC4 - UK Sovereign Base Areas