Korean defenses. When they finally arrived, the North Korean forces at Inchon had already surrendered, so the Blue Beach forces suffered few casualties and met little opposition. The 1st Marine Regiment spent much of its time strengthening the beachhead and preparing for the inland invasion.
Immediately after North Korean resistance was extinguished in Inchon, the supply and reinforcement process began. Seabees and Underwater Demolition Teams (UDTs) that had arrived with the U.S. Marines constructed a pontoon dock on Green Beach and cleared debris from the water. The dock was then used to unload the remainder of the LSTs.
Documents written by North Korean leader Kim Il Sung and recovered by UN troops soon after the landing said, "The original plan was to end the war in a month, we could not stamp out four American divisions… We were taken by surprise when United Nations troops and the American Air Force and Navy moved in."
On September 16, the North Koreans, realizing their blunder, sent six columns of T-34 tanks to the beachhead. In response, two flights from F4U Corsair squadron VMF-214 bombed the attackers. The air strike damaged or destroyed half of the tank column and lost one plane. A quick counter-attack by M26 Pershing tanks destroyed the remainder of the North Korean armored division and cleared the way for the capture of Inchon.
On September 19, the U.S. Army Corps of Engineers repaired the local railroad up to eight miles (13 km) inland. The Kimpo airstrip was captured, and transport planes began flying in gasoline and ordnance for the aircraft stationed at Inchon. The Marines continued unloading supplies and reinforcements. By September 22, they had unloaded 6,629 vehicles and 53,882 troops, along with 25,512 tons (23,000 tonnes) of supplies.
In contrast to the quick victory at Inchon, the advance on Seoul was slow and bloody. The NKPA launched another T-34 attack, which was trapped and destroyed, and a Yak bombing run in Inchon harbor, which did little damage. The NKPA attempted to stall the UN offensive to allow time to reinforce Seoul and withdraw troops from the south. Though warned that the process of taking Seoul would allow remaining NKPA forces in the south to escape, MacArthur felt that he was bound to honor promises given to the South Korean government to retake the capital as soon as possible.
On the second day, vessels carrying the U.S. Army's 7th Infantry Division arrived in Inchon Harbor. General Edward "Ned" Almond was eager to get the division into position to block a possible enemy movement from the south of Seoul. On the morning of September 18, the division's 2nd Battalion of the 32nd Infantry Regiment landed at Inchon and the remainder of the regiment went ashore later in the day. The next morning, the 2nd Battalion moved up to relieve a U.S. Marine battalion occupying positions on the right flank south of Seoul. Meanwhile, the 7th Division's 31st Regiment came ashore at Inchon. Responsibility for the zone south of Seoul highway passed to 7th Division at 6:00 pm on September 19. The 7th Infantry Division then engaged in heavy fighting on the outskirts of Seoul.
Before the battle, North Korea had just one understrength division in the city, with the majority of its forces south of the capital. MacArthur personally oversaw the 1st Marine Regiment as it fought through North Korean positions on the road to Seoul. Control of Operation Chromite was then given to Major General Edward Almond, the X Corps commander. It was Almond's goal to take Seoul on September 25, exactly three months after the beginning of the war. On September 22, the Marines entered Seoul to find it heavily fortified. Casualties mounted as the forces engaged in desperate house-to-house fighting. Anxious to pronounce the conquest of Seoul, Almond declared the city liberated on September 25 despite the fact that Marines were still engaged in house-to-house combat (gunfire and artillery could still be heard in the northern suburbs).
The last North Korean troops in South Korea still fighting were defeated when General Walton Walk