In late September 1950, after the Inchon landing, United Nations forces advanced slowly on Seoul against heavy, North Korean resistance.
The North Korean Peoples Army, attempting to stall the UN offensive long enough to reinforce Seoul and withdraw troops from the south, launched a T-34 tank attack against advancing UN troops and a Yak bombing run on Inchon harbor. The North Korean tanks were destroyed and the Inchon bombing run did little damage.
U.S Marines firing at North Korean snipers in Seoul – September 1950. Wikipedia
Entering Seoul, U.S. Marines encountered barricades and heavy resistance from North Korean machine guns, snipers and land mines as they fought house-to-house.
After Seoul was recaptured, South Korean authorities summarily executed many individuals along with their families suspected of sympathizing with the North Korea invaders. These extra-judicial killings coincided with the Goyang Geunjeong Cave massacre of 153 civilians by police in the Goyang, Gyeonggi-do district.