The entrance of the Bucheon International Animation Festival 2017 was closed after police received bomb threats against the venue on Oct. 20. (Yonhap)

Police are working to track down a man in his 30s believed to have made bomb threats against an event this month featuring South Korean girl group Apink.

An unidentified man made calls to emergency line 112, saying he had planted explosive devices at the opening ceremony of the Bucheon International Animation Festival 2017 on Oct. 20, according to police in Bucheon, Gyeonggi Province, Sunday.

The claim on Oct. 20 that he had left explosive devices in Korea Manhwa Museum, proved to be a hoax upon police investigation.

The same man is believed to have made several similar calls using identification restrictions to the museum previously.

The police are investigating the whereabouts of the suspect with the help of Korea Telecom and other telecommunications agencies. They have not yet identified him, but said he was a US citizen of Korean ethnicity who currently lives in Canada.

Several events across Korea this year featuring Apink were interrupted and postponed due to similar threats, which have included death threats against Apink members. The police believe that the same suspect is behind all these cases.

By Joel Lee (joel@heraldcorp.com)