Australia’s space agency has identified the likely source of six mysterious spherical objects that washed up on a Queensland beach over the weekend.

The agency said on Monday the objects appear to be pressure vessels from a foreign space launch vehicle that recently re-entered the atmosphere from orbit.

The objects were discovered on Forrest Beach, north of Townsville.

The agency said it was working with international authorities to formally confirm which launch vehicle they came from.

“The objects’ location and characteristics are consistent with debris from a foreign rocket body that recently re-entered the atmosphere from orbit,” the agency said in a statement.

Pressure vessels are spherical tanks used in spacecraft and rockets to store gases or propellants under high pressure. They are typically made from titanium alloys and are among the most structurally robust components of a launch vehicle, which is why they can survive re-entry and reach the ground or ocean intact rather than burning up.

Crews in protective suits were seen placing the objects into hazmat barrels under police guard over concerns they may contain residual amounts of hazardous substances.

Queensland’s fire department said a 50-metre exclusion zone remained in place around the area, urging anyone who found a suspicious object not to touch it.

“If you come across any suspicious objects in the area, do not touch them. Move away and call Triple Zero immediately,” it said.

The small coastal community of Forrest Beach, home to around 2,500 people, spent the weekend under heightened alert.

“It’s very quiet, not a lot happens here. So having a lot of extra activity – that definitely created a little bit of excitement,” Lisa Scobie, owner of Forrest Beach Takeaway, told public broadcaster ABC.

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