squad watched from hills south of Incheon, plotting locations where KPA machine guns were firing at the flotilla. They relayed this information to the invasion force via Japan in the afternoon. During the night of 13–14 September, Struble decided on another day of bombardment, and the destroyers moved back up the channel off Wolmido on 14 September. They and the cruisers bombarded the island again that day, and planes from the carrier task force bombed and strafed it. At 00:50 on 15 September 1950, Lieutenant Clark and his South Korean squad activated the lighthouse on the island of Palmido. Later that morning, the ships carrying the amphibious force followed the destroyers toward Incheon and entered Flying Fish Channel, and the US Marines of the invasion force got ready to make the first landings on Wolmido. Naval mine clearance Within weeks of the outbreak of the Korean War, the Soviet Union had shipped naval mines to North Korea for use in coastal defense, with Soviet naval mine warfare experts providing technical instruction in laying and employment of the mines to North Korean personnel. Some of the mines were shipped to Incheon. The UN forces did not become aware of the presence of mines in North Korean waters until early September 1950, raising fears that this would interfere with the Incheon invasion. It was too late to reschedule the landings, but the North Koreans laid relatively few and unsophisticated mines at Incheon. Destroyers in the assault force visually identified moored contact mines in the channel at low tide and destroyed them with gunfire. When the invasion force passed through the channel at high tide to land on the assault beaches, it passed over any remaining mines without incident. Battle Green Beach At 06:30 on September 15, 1950, the lead elements of X Corps hit "Green Beach" on the northern side of Wolmido. The landing force consisted of the 3rd Battalion, 5th Marines, led by Lieutenant Colonel Robert Taplett and nine M26 Pershing tanks from the USMC 1st Tank Battalion. One tank was equipped with a flamethrower and two others had bulldozer blades. The battle group landed from tank landing ships (LSTs). The entire island was captured by noon at the cost of just 14 casualties. The KPA defenders were outnumbered by more than six to one by the UN troops. KPA casualties included over 200 killed and 136 captured, primarily from the