Indonesia's nuclear authorities said on Monday they would investigate the radioactive contamination of a patch of land in a housing complex outside Jakarta, and called for calm.

The Nuclear Energy Regulatory Agency (Bapeten) issued a statement on Friday telling residents to stay away from a piece of land in Serpong, 43 km south of Jakarta, because it was contaminated. Local media said the land is next to a volleyball court.

Bapeten said it had discovered an elevated level of radioactive isotope Caesium-137 during a routine test for radioactivity in the area at the end of last month, causing alarm among some locals and raising questions about its source.