In the early 1920s, the patrol found itself fighting the forces of warlords and bandits. To accommodate its increased responsibilities on the river, the United States Navy constructed six new gunboats in Shanghai during 1926–1927 and commissioned them in late 1927–1928 during the command of Rear Admiral Yates Stirling, Jr. to replace four craft, originally seized from Spain during the Spanish–American War, that had been patrolling since 1903. All were capable of reaching Chungking at high water, and all year-round. Collectively referred to by the U.S. press as "the new six", and were the largest, and next in size, and and the smallest. These vessels gave the Navy the capability it needed at a time when operational requirements were growing rapidly.