'Group VIII' was a US special forces operation to land a 30-man Office of Strategic Services party, all of Greek ethnic origins, for operations in the western region of German-occupied Greece to aid local resistance forces (15 July/20 November 1944).

The party was commanded by Captain R. Darr with Lieutenant D. E. Mort as second in command, and on 15 July boarded an infantry landing craft at Monopoli in south-eastern Italy and landed near the mouth of the Akheron river during the night of 16/17 July. Between 18 and 20 July, the US personnel moved themselves and all their equipment from beach in an eight-hour shuttle operation into the mountains. More than one-quarter of the equipment was lost as no one had made provision for it to be guarded. In the period between 21 and 27 July the party moved farther, this time to Romanon, despite a shortage of mules.

On 28 July the 'Group VIII' party joined the 'Group I' party, and both moved to Radhovisi. The two groups undertook a joint ambush operation on 18 August before returning to Romanon on 26 August. The two groups then divided on 31 August, and the 'Group VIII' party then spent the time up to 8 October reconnoitring and planning possible operations.

On 8 October, the US party, 200 Andartes and British personnel of the Raiding Support Regiment established an ambush on the railway and parallel road linking Agras and Arris. On the next day a German force of 200 infantry, a Panzerzug (armoured train) and eight trucks approached the position. Andarte fire pinned the German infantry, and the train and trucks stopped out of sight of the Raiding Support Regiment. German light guns and mortars returned the Greek fire. A small railway carriage and two trucks with cannon mounted on them approached and were immediately destroyed by the anti-tank guns operated by the men of the Raiding Support Regiment. In five minutes the British party had expended its anti-tank gun and mortar ammunition, and withdrew. Over a period of 30 minutes, the US party pulled back some 600 yards (550 m) but then held firm for the rest of the day. The Germans withdrew late in the afternoon after losing eight men killed and more than 50 wounded. Two days later the Germans abandoned and destroyed Agras station and two railway bridges as they retreated toward Edessa.

Between 9 October and 7 November the US party undertook only small-scale harassing efforts which resulted in about 10 German casualties and the destruction of several vehicles. Reconnaissance was continued, but there were no major operations.

On 20 November the group was evacuated by air from Ardea to Bari.