During a routine check to make sure that its mobile radiation detection unit was working properly, the nuclear energy regulatory agency of Indonesia, known as BAPETEN (Badan Pengawas Tenaga Nuklir) discovered an unusually high reading in a vacant lot near a housing complex.

BATAN (Badan Tenaga Nuklir Nasional), a separate research agency, calmed some nerves of people in an adjacent housing complex in South Tangerang, Banten. The BATAN agency spokesperson, Heru Umbara, advised that “relevant authorities” were handling the case.

Heru issued a statement Saturday that said, "Residents can carry out activities as usual, as long as they do not enter the area that has been marked as contaminated. If managed properly, exposure to this radiation will not endanger the residents."

A day earlier, BAPETEN spokesperson Indra Gunawan said in a statement, “From Jan. 30 to 31, BAPETEN conducted a function test with target areas of Pamulang, the Puspiptek [Center for Science and Technology Research] housing complex, the Muncul area, the ITI [Indonesia Institute of Technology] campus, the Batan Indah housing complex, and the Serpong train station.”

The statement continued, “A joint BAPETEN and BATAN team conducted a search to find the source of the high radiation on Feb. 7 to 8 and found several radioactive fragments. Based on those results, we concluded that the contamination had spread in the area and decontamination efforts had to be conducted by removing or dredging contaminated soil and removing contaminated trees and other vegetation.”

Gunawan said after the fragments were removed, tests showed that the radiation levels in the area had decreased but were still above normal levels.

Another BAPETEN spokesperson, Abdul Qohhar Teguh, told the Jakarta Post that the agency was not yet able to confirm the source of the radioactive fragments. He said, “For the time being, we have not focused on investigating the location of the source, where it came from, why it was there, who brought it. At the moment the joint team is still focusing on clearing the scene.”

Qohhar added that the radiation did not come from a leak from some small reactors located about 3 miles away in another building and used for experimental purposes.

The spokesperson went on to explain that the material found was Cesium-137 and that any nuclear accident akin to the ones in Chernobyl or Fukushima would have left other substances. Qohhar added that the exposure rate is far below the threshold where people would show any symptoms or become ill.

As BATAN continued with the cleanup of the contaminated lot, one resident of the housing development told the Jakarta Post, “I think there is no need to panic. I believe that the authorities are doing their best to solve the problem. And if they thought it was dangerous, they would have warned us. But so far there is still no warning, so we’re safe.”

Heru from BATAN said that testing would be conducted on residents near the exposed area to measure their bodies’ radioactivity levels.