In Italy, on the night of 8th/9th April, 1945, Major Lassen was ordered to take out a patrol and raid the north shore of Lake Comacchio. His task was to cause casualties, capture prisoners and give the impression of a major landing. The patrol was challenged and came under machine-gun fire. Major Lassen himself attacked with grenades and silenced two enemy posts, capturing two prisoners and killing several Germans. The patrol had suffered casualties and was still under fire. Major Lassen moved forward and flung more grenades into a third enemy position, calling upon the enemy to surrender. He was then hit and mortally wounded, but whilst falling he flung a grenade, wounding more of the enemy and enabling his patrol to capture this last position. Finally, he refused to be evacuated lest he should impede the withdrawal and endanger further lives. His high sense of devotion to duty and the esteem in which he was held by the men he led, added to his own magnificent courage, enabled Major Lassen to carry out with complete success all the tasks he had been given.