Even as Rojo ordered the Republican concentration at Caspe, the Italians were approaching Alcañiz, and the Republican rout became absolute. Even where a Republican unit would fight effectively, it had to fall back because of the collapse of neighboring units. Entire units fell apart and desertions became rife. The Italian and German airplanes controlled the skies; their bombers attacked the fleeing Republican units with aerial protection from modern fighters. Karol Świerczewski, known as General Walter, commander of the International Brigades, barely escaped capture at the fall of Alcañiz. Finally, after two days of heavy fighting, Caspe fell on March 17 to Varela's attacking army. The International Brigade performed valiantly in the defense, but was driven off. After eight days, the Nationalists were 70 miles (113 km) east of the positions they had held when the battle started. This first part of the offensive punched a huge hole in the front, created a salient from Belchite to Caspe to Alcañiz and back to Montalbán.