It was called "Ratweek"; and for the target duration of one week it was possible by action in all areas to paralyse all movement of enemy men and supplies on practically every length of line in Jugoslavia, whether in Slovenia, Croatia, Serbia, Macedonia, or elsewhere.
[3]In the summer of 1944, Allied commanders realised that the German offensive in the Balkans was slackening, and that they may cut their losses and withdraw to a more easily tenable defence line in the north, abandoning the region altogether.
Finally, the Royal Navy destroyers and the MTBs engaged on the sea lanes of the Adriatic coast, now in extensive use by the Germans as an alternative way out of the southern Balkans.
[9] The plan was for the Partisans to attack the two points north and south of Leskovac, while the town, the seat of a large German garrison, would be left to the Allied air force.
On 6 September, the day of the proposed attack, an urgent message from William Elliot arrived stating that the air reconnaissance confirmed the presence of a strong concentration of armour and motor transport in town.
Soon after, an air force of fifty Flying Fortresses bombed the town heavily in a surprise attack, reducing much of it to rubble with a large number of civilian casualties.
[15] In total, over 100 locomotives were destroyed, together with many trunk railway lines, forcing the enemy onto the roads where fuel and truck shortages left them vulnerable to further attacks.
At the same time, the Luftwaffe in Yugoslavia was crippled, losing 94 aircraft, while the Long Range Desert Group, the Special Boat Service and the Royal Navy attacked targets along the Adriatic coast.
Maclean was planning to spend more time in Serbia preventing German withdrawal, but in the second half of September, he received a personal signal from General Wilson.