This was a German unrealised air attack, using ‘Mistel’ composite aircraft and explosive-laden Dornier Do 24T flying boats, against the bridges over the Vistula river being used by the Soviet forces as they advanced through Poland and into eastern Germany (April 1945).
The undertaking was intended to sever the the primary logistical lines of communication of the Soviet forces advancing to the west in the direction of Berlin, and thus decisively slow their progress.
For this mission four Do 24T flying boats were adapted to attack the Vistula river bridges at Warsaw, Toruń, Dęblin and Dunjawec near Kraków. The 'boats were to be landed on the water close their targets, whereupon their pilots would abandon the 'boats and make for the shore in a small boat, leaving the explosive-laden 'boat to be controlled by a member of the 'Leonidas' Staffel. The object was for the 'boat strike one of each bridges primary piers, which would be destroyed by the resulting blast and triggering the collapse of the entire structure.
'Aktion 24' was not implemented, largely as a result of the fact that a raid by Consolidated B-24 Liberator heavy bombers on the German base destroyed three of the four 'boats.