The Australian Space Agency (ASA) says it has “identified the likely source” of mysterious large balls that had washed up on a beach in northern Queensland this weekend.

The six solid objects discovered on Forrest Beach, to the north of Townsville, were thought to be space debris. The ASA said on Monday that they “appear to be pressure vessels from a space launch vehicle”.

The agency added that it was working with international authorities to formally confirm the launch vehicle.

Queensland’s fire department said on Sunday that a 50m exclusion zone remained in place, urging anyone who found a suspicious object in the area not to touch them.

It said members of the public who encounter them should immediately move away and call the emergency services.

There was some speculation online that the spheres were propellant tanks for spacecraft, and so could contain residual amounts of a highly flammable or reactive substance.

Crews in protective suits were reportedly seen placing the spheres in hazmat barrels under police guard, over concerns they may contain hazardous substances.

Forrest Beach Takeaway owner Lisa Scobie said the local community was curious to know their origin.

“It’s very quiet, not a lot happens here. So having a lot of extra activity… that definitely created a little bit of excitement,” she told public broadcaster ABC.

According to the ASA’s latest statement, “the objects’ location and characteristics are consistent with debris from a foreign rocket body that recently re-entered the atmosphere from orbit”.

It is not the first time that such mysterious objects have been spotted on Australia’s shoreline.

In 2023, India confirmed that a giant metal dome that washed up on a Western Australian beach near Perth was from one of its rockets.

India’s space agency spokesman later told the BBC that it was from one of its Polar Satellite Launch Vehicles (PSLV).

A spherical object similar to those discovered this weekend was also found in remote grassland in Namibia, southern Africa, in 2011.

Experts at the time said they believed it was most likely a fuel tank or bladder tank containing hydrazine – a highly volatile propellant – from an unmanned rocket.