South Korean riot police stormed the country’s biggest shipyard and arrested striking workers whose dispute has paralyzed production for over three months. At first light, under cover of a barrage of tear gas, thousands of police in combat gear assaulted the strikers’ stronghold in the yard of Hyundai Heavy Industries Co. at Ulsan, on the southeast coast. Later, police again fired tear gas to evict about 1,000 strikers who had been staging a sit-in at a nearby company dormitory, demanding reinstatement of 55 strike leaders fired last week. The strikers fought back with rocks and clubs but were soon overpowered. Witnesses said scores were hauled away.