A large and potentially hazardous mystery object has washed up on a remote Western Australian beach, prompting a police investigation to identify it.

Officers are guarding the item, which is understood to be a large cylindrical piece of equipment made of a woven material about two metres high.

Multiple state and federal agencies have been called in to help determine what it is and where it came from.

The barnacle-encrusted rusty object was found on Sunday near Green Head, about 250 kilometres north of Perth.

It quickly drew a crowd of interested locals, some posing for photos with the device before authorities arrived.

Local resident Garth Griffiths said a neighbour alerted him to the strange find on Sunday.

“Sometime yesterday a local lady and her partner discovered it just floating on the edge of the water and dragged it out with their four-wheel drive,” he told the ABC.

“It’s a sort of semi-cylindrical object, made of light carbon fibre material like lightweight resin.

“Sort of 2.5 metres across by 2.5 to 3 metres long.”

A cordon has been set up around the mechanism, which some Reddit users speculated could be Indian space junk.

Authorities are treating the device as dangerous and have ruled out an aviation link.

“At this early stage it appears the object did not originate from a commercial aircraft,” a police spokeswoman said on Monday.

The public has been warned to keep a safe distance from the object.

“This measure has been taken to ensure the preservation of potential evidence and facilitate further expert examination,” the spokeswoman said.

“The investigation is ongoing, and until further information is available, we urge everyone to refrain from drawing conclusions.”

Despite that request, Mr Griffiths said “Google sleuths” had been busy trying to work out what the object was.

“There were barnacles and marine life growing on it. [It] may not be too dangerous and maybe our shire might need to bill Boeing or Lockheed [airline companies] or someone for dropping space junk on our beach,” he said.

-with AAP