After the fall of Mount Suribachi in the south, the Japanese still held a strong position throughout the island. General Tadamichi Kuribayashi still had the equivalent of eight infantry battalions, a tank regiment, two artillery, and three heavy mortar battalions, plus the 5,000 gunners and naval infantry. With the landing area secure, more troops and heavy equipment came ashore and the invasion proceeded north to capture the airfields and the remainder of the island. Most Japanese soldiers fought to the death. On the night of March 25, a 300-man Japanese force launched a final counterattack led by Kuribayashi. The island was officially declared secured the following morning.