The Japanese tried to take the south gate of Busan Castle first but took heavy casualties and were forced to switch to the north gate. The Japanese took high ground positions on the mountain behind Busan and shot at Korean defenders within the city with their arquebuss until they created a breach in their northern defenses. The Japanese overwhelmed the Korean defenses by scaling the walls under cover of the arquebuses. This new technology destroyed the Koreans on the walls. Again and again the Japanese would win battles with arquebuses (Korea would not begin to train with these firearms until the Korean General Kim Si-min forged them at a Korean armory). General Jeong Bal was shot and killed. Morale fell amongst the Korean soldiers and the fort was overrun at around 9:00 in the morning—nearly all of Busan's fighting force was killed. The Japanese massacred the remaining garrison and non-combatants. Not even animals were spared. Yoshitoshi ordered his soldiers to loot and burn valuable items. The Japanese army now occupied Busan. For the next several years Busan would be a supply depot for the Japanese. The Japanese continued to supply troops and food across the sea to Busan until Korean Admiral Yi Sun-sin attacked Busan with his navy.