The South Korean police on Thursday launched an investigation into what appear to be fraudulent emails sent to South Korean officials, which claim to be requesting advice on North Korea’s recent nuclear test.

The emails impersonated key South Korean offices, including the Office of National Security, Office of Senior Secretary to the President for Foreign Affairs and National Security, Office of Director-General for Policy Planning (under the Ministry of Foreign Affairs) and the Unification Policy Office, South Korean police told local media on Thursday.

Police officials raised the possibility that the emails might have been part of a hacking attempt