An office worker in his 30s was apprehended on Tuesday, a day after writing an anonymous post as a police employee on a popular online platform declaring that he would commit a mass stabbing near Exit No. 1 of Gangnam Station in Seoul.

According to the National Police Agency, the suspect was caught near his home at 8:32 a.m. on Tuesday. The suspect is accused of writing a post on Blind, an online community and forum for verified employees.

“I'm going on a mass stabbing at Gangnam Station Exit No. 1," the post read. "Put yourself on guard. I’m going to kill everyone.”

The post was deleted almost immediately, but went viral online as a screen capture. It also caused more of a stir compared to other murder threats, as it was written by a user presumed to be an active police employee. This prompted National Police Agency Commissioner General Yoon Hee-keun to order a swift investigation.

However, according to police officials, it was found that the suspect was not a current police employee, nor a former one.

It is unclear as to how the suspect signed up for Blind as a National Police Agency employee, as users must verify themselves through their workplace email when making their account. Blind allows all users to write their posts anonymously but includes information that reveals the writer’s workplace.

Screen captures of the posts that the suspect wrote previously have also gone viral online. Some of his posts read, “Is anyone willing to take nude pictures of me? I like feeling humiliated,” and “Let’s be friends and I’ll give you 200,000 won. I’m handsome and nice and will pay for everything we do together.”

The police will investigate the suspect’s motives, and are reviewing the possibility of charging him for impersonating a public worker.