North Korea's satellite images have revealed activities at its Yongbyon site which indicate a possible restart to a reactor that could provide it with weapons-grade plutonium, the UN atomic agency said.
The International Atomic Energy Agency (IAEA) head, Yukiya Amano, said that they continue to monitor developments at the Yongbyon site, which included the release of steam from two vents and the apparent discharge of cooling water, and they indicate testing ahead of a restart, News24 reports.
However, Amano denied of drawing any conclusion, saying that they do not have inspectors on the ground to confirm anything.
North Korea had kicked out IAEA inspectors in 2009, the report added.
The country has been carrying out nuclear tests since 2006, but Yongbyon was shut down in July 2007.
However, the release of satellite imagery by the US-Korea Institute at Johns Hopkins University and the Institute for Science and International Security last month also showed activity at the site.