Two Vietnamese ships have been caught illegally fishing in the Great Barrier Reef Marine Park.

The boats, carrying 28 crew members, were intercepted by Australian Border Force officials at the weekend.

The men were caught with a large amount of diving gear and hundreds of kilograms of what is suspected to be illegally caught sea cucumbers.

The two ships were initially spotted from the air, before they were intercepted and boarded by officers from HMAS Childers and ABFC Roebuck Bay near the Lockhart River region, between the Torres Strait and Cooktown.

The vessels were towed to Cairns where further investigations will be undertaken by the Australian Fisheries Management Authority.

The 28 men are expected to be placed into immigration detention in the meantime.

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Lockhart River Mayor Wayne Butcher said he was unaware of any previous activities involving illegal fishers accessing the remote waters.

"It's a very rich environment for fisheries...for foreigners to get past the gate and tap into our resource, that's just an extra burden on our fisheries," he said.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Listen Duration: 4 minutes 40 seconds 4 m 40 s Mayor Wayne Butcher raises questions about border security in Australia's far northern waters after illegal fishers were caught off Cape York Peninsula ( Charlie McKillop ) Download 2.1 MB

"It's a bit frightening in one sense if they can sneak through the Torres Strait and get down (here) because we're one of the last communities on the east coast of Australia. We're in the middle of nowhere here."

Mayor Butcher said Cape York residents took their role as part of the coastal surveillance network very seriously, but the recent incursion had raised questions about the effectiveness of border protection in the region.

"It doesn't seem too effective if two vessels with 28 people on board have been able to sneak so far down the Australian coastline," he said.

"Looking at the influx of boat people and now looking at the fishing fleet coming so far down the Cape now, I think there's probably some alarm bells ringing there."