On June 16 of that same year, Lenas joined Markos Drakos in an unsuccessful attempt to assassinate Cyprus governor Robert Armitage. Afterwards, he had to flee to the mountains where he joined the guerrila forces headed by Grigoris Afxentiou. Lenas concentrated his activities in the Pitsilia area and became an expert in the manufacture of MK2 type hand grenades.
On February 17, 1957, Lenas was ambushed by the British near his hideout at Potamitissa and was wounded in the battle that ensued. He died on March 28, 1957 and was buried in the yard of the Central Jail of Lefkosia.