I watched, crabs digging burrows in the sand on the beach, in and out of the hole while carrying sand with claw arm and throwing it out. The movement is very fast and done repeatedly. I shot photos and videos, from a video footage source I made it into GIFs Animation.

Search results on the internet, these animal called Ghost Crab of the subfamily Ocypodinae.

They are common shore crabs in tropical and subtropical regions throughout the world, inhabiting deep burrows in the intertidal zone. They are generalist scavengers and predators of small animals. The name "ghost crab" derives from their nocturnality and their generally pale coloration. They are also sometimes called sand crabs, though the name refers to various other crabs that do not belong to the subfamily. ^{[Source: en.wikipedia.org]}

I found them on the beach in Lhokseumawe City, this animal is commonly found on the coast of Sumatra island, we in Aceh named it keurungkong.

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