“Based on data received from the Global Environmental Monitoring System, there’s an increase in background radiation in the South China Sea in connection with a radiation incident,” Rospotrebnadzor said in an online statement.

The Russian government’s consumer protection watchdog Rospotrebnadzor said Friday it has detected a “radiation incident” in the South China Sea.

It added that the radiation levels did not “currently threaten the Russian population” and that it “has increased its radiation monitoring in the adjacent border areas.”

A website run by far-right U.S. talk show radio host Hal Turner claimed Wednesday that unidentified military sources had allegedly detected an underwater nuclear explosion in the area that caused powerful shockwaves. The U.S. tech news website Gizmodo cited two scientists who dismissed the report as fake.

Gizmodo reported that uRADMonitor Global Environmental Monitoring Network data used in the initial report registered “negligible” radiation and noted that two other agencies in the region showed normal radiation readings.

Military analysts reported Saturday that an 11,000-ton Chinese nuclear missile submarine had surfaced among Vietnamese fishing boats in the South China Sea in September.