YTN TV reported that the man screamed "South and North Korea should be reunified" during the attack. The rival Koreas have been divided for decades along the world's most heavily armed border. The U.S. stations 28,500 troops in South Korea as a deterrent against North Korea, and some South Koreans see the U.S. presence as a barrier toward a unified Korea.
South Korean police reportedly detained the assailant—a 55-year-old man identified only as Kim—immediately after the attack. According to the Korea Herald, he had previously served a suspended sentence for throwing a block of concrete at a Japanese ambassador.