Police have apprehended 67 people suspected of making online threats of public killings as of Tuesday morning.

The National Office of Investigation(NOI) under the National Police Agency announced on Tuesday that as of 9 a.m., the number rose by two since 6 p.m. the day before.

However, 52-point-three percent of those apprehended through the end of Monday were in their teens, many under the legal age of criminal liability of 14 and therefore not eligible to be charged.

Online threats of terror attacks have begun to emerge following a deadly stabbing rampage in Seoul's Sillim area on July 21, which killed one person while injuring three others.

The number of such threats spiked after another stabbing spree and vehicular attack in the Gyeonggi provincial city of Seongnam last Thursday that killed one person and injured 13 others.

The police are expected to charge suspects for intimidation and obstruction of justice through deception.