The Air Crew Rescue Unit was formed in summer 1944 to evacuate Allied airmen forced down in either Partisan or Chetnik territory in Yugoslavia. Lt Nick Lalich (left), team leader of the “Halyard” Mission with Lt Mike Rajacich (right), is interviewing a P-51 pilot who was shot down south of Belgrade in September 1944. Their names are a reminder that the OSS sought out Americans of suitable national heritage to operate in particular countries. Rajacich wears British parachute wings on his left chest, while Lalich has a British holster. (NARA)

LIAISON WITH THE PARTISANS; CENTRAL YUGOSLAVIA, FALL 1943
Intelligence from deep within enemy territory was obtained by OSS liaisons with resistance groups such as Tito’s Partisans (though the quality of the intelligence was at the mercy of the Partisans who provided it, and who saw it as a form of leverage.) This agent has started to prepare a coded message for his SSTR-1 suitcase radio. Although this was a successful design the power supply was a constant challenge; operators found that it used less battery power when transmitting than receiving messages. Inserted with a uniformed paramilitary group rather than operating undercover, this operator has no need to wear civilian clothing.

The OSS found itself in the middle of a quasi-civil war in Yugoslavia between Josip Tito’s Communist Partisans and Gen Draza Mihailovich’s royalist Chetniks. In order to assess all local efforts against the Axis occupation and to obtain intelligence in-country, in August 1943 OSS liaison officers were parachuted in to both these guerrilla movements to report on their activities and capabilities. In October 1943 MU gathered a small fleet of schooners and other cargo vessels at the Italian ports of Bari and Monopoli, and shipped supplies to the Partisan-held island of Vis off the Yugoslavian coast until January 1944. Some of the Allied arms supplied to Tito were not used against the Germans, as several OSS personnel with the Chetniks discovered. From January to August 1944 OG teams and British Commandos conducted several reconnaissance and raiding operations in the Dalmatian Islands to harass the German garrisons. The first penetration of the Third Reich by the OSS occurred in June 1944, when Maj Franklin Lindsay and a band of Partisans crossed into an annexed portion of northern Slovenia, successfully blowing a 150ft gap in a stone viaduct bridge and cutting an important rail line for the rest of the war.

At the Tehran Conference in November 1943 the decision was taken to cease all aid to Mihailovich and instead to fully support Tito; the reason was the Chetniks’ less than aggressive guerrilla campaign, and charges of collaboration with the enemy. Mihailovich claimed that a lack of supplies and fear of wholesale reprisals against civilians prevented him from fighting the Germans at the level the Allies demanded, but the decision stuck, and the OSS was forced to withdraw its last liaison officer with the Chetniks in May 1944. That summer, however, a large number of American airmen continued to bail out over Chetnik-held areas. In collaboration with the USAAF, the OSS established the ACRU that parachuted into Chetnik territory in August 1944; the unit built a rough airstrip that enabled C-47s to evacuate over 500 Allied airmen by the time it departed in December.

When the Red Army crossed into Yugoslavia in September 1944, and as more territory came under Partisan control, Tito imposed severe restrictions on the movement and activities of the OSS teams that prevented them from gathering any useful intelligence for the rest of the war. The OSS established a mission in Belgrade after it was liberated in October 1944, and reported on political, economic, and medical conditions there before withdrawing in July 1945.