During the
Cyprus Emergency, in which the Greek-Cypriot organization
EOKA waged a guerrilla campaign against
British colonial rule in Cyprus from 1955 to 1959, Sampson joined EOKA and adopted the
nom de guerre Atrotos (), or "Invulnerable". Sampson joined EOKA and formed part of an execution team under the direct orders of General
Georgios Grivas ("Digenis"), leader of EOKA. Another member of this team was
Neoptolemos Georgiou who was later arrested for various activities whilst being a member of
EOKA-B. Sampson and Georgiou participated in a number of murders carried out along Ledra Street in
Nicosia, which was nicknamed "Murder Mile", and shot dead numerous British servicemen and police officers. He was involved in at least 15 killings. According to British sources, the actual number was much higher. Among his victims were three police sergeants, and in May 1957, Sampson was tried for one of their murders. He confessed, but was acquitted on the grounds that his confession may have been coerced by torture. At the time, Sampson was working as a journalist, and he would often photograph the bodies of his victims after killing them, then send the photographs to
The Cyprus Times newspaper to be published. The police became suspicious about how Sampson was always the first reporter to arrive at the murder scene and he was arrested. Only a month after his acquittal, he was given away by informants and arrested in the village of Dhali. He was convicted of weapons possession which, under the emergency regulations in effect at the time, carried a death sentence. The death sentence was subsequently commuted to life imprisonment and Sampson was flown to the United Kingdom to serve it. A year and a half later, under a general
amnesty as part of the 1959
Zürich and London Agreement, he was released but he remained in
exile in Greece until Cyprus gained formal independence in August 1960. He returned to Nicosia shortly after
Independence Day. ==Post-independence==