Police intensified their investigation Saturday into a wave of online posts threatening copycat crimes following a recent stabbing rampage at a department store.
On Thursday afternoon, a man drove a car onto a sidewalk and attacked people with a knife at a department store in Seongnam, south of Seoul, leaving 14 people wounded.
Since the incident, at least 42 posts warning of similar crimes had appeared on internet communities and social media sites as of 7 a.m. Saturday, the National Police Agency said.
As of 7 p.m., the police had apprehended a total of 30 people responsible for such posts, including teenagers.
On Friday, three people were detained in Seoul for making online threats of copycat crimes. Among them was an underage person who threatened to kill five people at a school entrance.
In Hanam, east of the capital, a 14-year-old middle school student was held for posting a murder threat.
On Saturday morning, a post predicting a knife attack at the Incheon Pentaport Rock Festival in Incheon, 30 kilometers west of Seoul, surfaced briefly online before being removed.
On Friday afternoon, the police arrested a man in his 40s who was wandering the streets of Yongin, about 40 kilometers southeast of Seoul, with a kitchen knife. He is suffering from a mental disorder, officials said.
In response to heightened public anxiety, the police bolstered security measures across the country.
More than 12,000 officers were deployed to patrol 247 locations nationwide, including subway stations and department stores, while 107 SWAT members equipped with firearms were dispatched to 43 densely populated areas, the police agency said.
Yoon Hee-keun, commissioner general of the National Police Agency, deplored a "social loss," saying that such posts threatening copycat crimes are worrying many people and also "wasting" police resources.
"We urge people to refrain from writing irresponsible online posts threatening murder," Yoon said after an onsite inspection of a "special policing" operation,
Police said Friday they will beef up patrols and stop and search operations for suspicious people on the streets in the wake of back-to-back mass stabbings, declaring a "special policing" operation.
Source: Yonhap News Agency