On 20 December, Wisconsin participated in a coordinated air-surface bombardment of Wonsan to neutralize pre-selected targets in its area. The ship shifted its bombardment station to the western end of Wonsan harbor, hitting boats and small craft in the inner swept channel with her 5-inch (127mm) guns during the afternoon and helping forestall attempts to assault the friendly-held islands nearby. Wisconsin then made an anti-boat sweep to the north, firing her 5-inch batteries on suspected boat concentrations.