Meanwhile, another Vietnamese column quietly moved west of the mountains. After bitter fighting, the Cham withdrew their lines from the coast to inland, where they realized that they had been surrounded by invaders from three sides: from the north, from the western mountains, and from the sea. The Vietnamese continued to advance, using gunpowder superiority to curb war elephants, pushing the Cham army toward the capital of Vijaya (Cha Ban). Nearby Thị Nại citadel on the coast was captured on March 18, and 400 Cham were killed. Thánh Tông then converged his armies to surround the city of Vijaya, where the Champa king was seeking refugee inside. According to Vietnamese sources, the Cham king Trà Toàn apparently tried to compromise and make an agreement for his kingdom's surrender, but Thánh Tông ignored and pressed on the siege.
