A U.S. media outlet says there has been active movement of people and vehicles within the two Koreas' now-shuttered industrial park in North Korea's border town of Gaeseong.

Citing satellite images taken on October 25, Voice of America(VOA) reported on Friday that people and objects were detected in at least 12 places near the electrical and electronics and textile production zones inside the complex.

Objects were laid down in rows in certain areas, and five to seven people were seen surrounding another object. A blue vehicle was spotted inside the western entrance.

According to satellite image service provider Planet Labs, images from this month showed objects being moved or their forms changing.

Nick Hansen, an affiliate researcher at Stanford University's Center for International Security and Cooperation, said on Thursday that the objects on the ground seem to be drying, suggesting that it could be grain.

South Korea's Unification Ministry said on Friday that while there has been movement at the complex in the past, none of the recent movements have been confirmed.