SEOUL - North Korea looks set to destroy its only known nuclear test site in front of international journalists probably later on Thursday (May 24), reported South Korea's official news agency Yonhap.

A group of reporters and television crews from South Korea, the United States, China, Russia and Britain are apparently still on their way to the remote north-eastern area of Punggye-ri after leaving Wonsan, an eastern port city, by train on Wednesday evening.

The train left Wonsan at around 7 pm (local time) for a journey expected to take 11 to 12 hours, followed by a four-hour bus ride and a mountain hike of more than an hour to the nuclear test site, according to a pool report sent by South Korean journalists.

The pool report was sent on Wednesday night. There has been no update yet.

The North earlier said it would dismantle the underground tunnels and other facilities at the Punggye-ri complex by explosion.

It has yet to announce a date and time but said it could happen between May 23 and 25 depending on weather.

The fact that the foreign media guests are making their way to the site suggests that the event is imminent, according to Yonhap.

The reclusive North is unlikely to let the visitors stay for a long time at the site where all six of its nuclear tests were conducted.

The weather is also forecast to be relatively good for the coming hours in the region, with rain showers predicted to start late Thursday.

It's unclear whether the North's leader Kim Jong Un will also visit the site to observe the closure of the facilities, a symbol of the communist nation's nuclear programme.