Residents were left terrified when thousands of worms appeared in the shallow part of a beach near their homes in the Philippines last month.
Footage shows the blue and brown creatures wriggling in the water as locals watched nearby in Cabugao, Ilocos Sur province on March 30.
Children first noticed the worms around 7pm while playing near the water and called their parents to have a look.
Carl Rebogio, an uncle of one of the kids, said the creatures gradually grew in number as the current pushed more of them onto the sand.
"We don’t know where they came from but it seemed like the water pushes them to the shore," he said.
"The children found them while playing and called us to inspect.
"It was the first time this happened in our area."
The worms were estimated to be at least 25 centimetres-long and had hundreds of limbs on their body like a millipede.
Jomeri added that the worms were gone after three hours and did not know where the creatures went.
"We checked again around 10pm and all the worms were gone. The water here is not polluted so that may not be the reason," he said.
As fishermen feared the incident could affect their livelihood, local official Nereo Daproza sought help from the Bureau of Fisheries and Aquatic Resources so they could investigate.
"Some of the residents were able to take some of the worms and were given to the agency so they could identify what it is," he said.
The agency had not yet released the result on their findings and in the meantime warns residents not to touch the worms in case they return as they might be toxic and dangerous to their health.
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