For 69 years, Jack Mann has refused to talk about what he did in the war.

As a member of the Special Boat Service, his missions behind enemy lines were shrouded in secrecy. Until now, he and his erstwhile comrades have kept those secrets but Private Mann, the last SBS fighter alive, has now spoken about his covert operations.

The soldiers who undertook secret operations were also known as Churchill's secret warriors - he wanted them to "set the lands of the enemy ablaze" - they attacked German and Italian positions in the Mediterranean theatre, in small teams behind enemy lines.

They wore no uniform, blending in with local communities, waiting for the moment to strike. If they were captured, they knew their commanders would deny all knowledge of their existence, and they would be treated as spies, suffering the consequences.

One of their most celebrated missions was Operation Postmaster in 1942, a raid on a German depot refuelling and rearming U-boats off the West African coast. The SOE boarded and made off with a number of German and Italian ships while their captains were ashore on the island of Fernando Po being entertained by a businessman - in reality a British secret agent.

Trooper Mann, who was a radio operator on the mission, said: "Fighting was never my speciality but I was in the middle of it. Each patrol would have a radio operator with them… How are you going to escape with no radio?"

The 90-year-old, born in Egypt, decided to join the army in his late teens after he learnt about the Shoah: "One of my uncles was a big Zionist and he heard about how Hitler was killing Jews and I said I was going to help.

"I joined the army and British intelligence soon heard I had skills with languages and came to me.

Mann said: "The Germans had strict instructions from Hitler himself to 'catch that group and kill them'. They killed three of our boys. After the war, a kernel went back to find the people who killed them and they did."