A fire broke out at the Savannah River National Laboratory, located within the US Department of Energy's nuclear complex in South Carolina, releasing radioactive material, infohub.kz reports.

An emergency was declared at the site. The blaze was accompanied by an "unfiltered release of radioactive material at ground level." The fire has been extinguished.

According to News 12, there is no threat to the public beyond the sprawling site — no signs of radioactive contamination have been detected outside the complex. The laboratory itself confirmed the same information.

Employees said those in Area A were forced to shelter behind barricades for about 30 minutes. They were later allowed to leave the site, though access remained closed to everyone else.

The US Federal Aviation Administration announced a temporary ban on flights over the site and its surrounding area, the broadcaster reported.

The Savannah River Site (SRS) is a US Department of Energy complex covering about 310 square miles that conducts research into nuclear materials, environmental cleanup and related technologies. It serves both as a site for cleaning up the legacy of past operations and as an active center for national security and nuclear technology research.

According to News 12, the complex was built in the early 1950s at the height of the Cold War. It was originally called the Savannah River Plant and was intended to produce key materials for nuclear weapons.