Amid the police announcing measures to ensure public safety following a stabbing spree in Gyeonggi Province's Bundang District on Thursday, at least 15 posts threatening similar attacks were flagged in online communities nationwide.

Police said on Friday that it confirmed at least 15 such threats on the day the National Police Agency vowed to sternly deal with people who upload such posts.

Of the 15 threats, 12 were posted after 6 p.m. Thursday and listed locations around Seoul as the possible scenes of random killings, including the subway stations of Jamsil and Gangnam as well as Yongsan District.

Police found that shortly after the stabbing rampage occurred in Bundang, threats of copycat crimes in nearby regions on Friday spread online rapidly between 6 and 8 p.m.

The Seomyeon subway station in Busan was also mentioned in a threat.

Police sent units to the mentioned locations to be on the lookout for any signs of crimes.

Since a stabbing rampage left one man dead and three wounded near Sillim subway station in Seoul's Gwanak District on July 21, police have come across at least 25 threats of random killings, leading to the apprehension of two individuals as they continue to track down the other posters.