 With both the Canadian and New Zealand Divisions finding progress difficult , it was decided to bring the Indian 21st Infantry Brigade into the attack with orders to seize <unk> . With no river crossing available , the Indian engineers rushed to build a bridge across the Moro which was completed on 9 December and allowed infantry and supporting armour to cross and expand the bridgehead on the far bank . The bridge was named the " Impossible Bridge " because the local geography required for it to be built backwards from the enemy bank of the river . 
