At least ten Indonesians who were meditating on a beach died in the night from Saturday to Sunday swept away by strong waves, according to the police.
They were part of a group of 23 people who meditated while holding hands on a beach in Payangan, East Java province.
"
They were too close to the sea and couldn't save themselves when the tidal wave swept them away
," local police chief Hery Purnomo told TVOne.
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Ten bodies were recovered from the ocean and 12 people were rescued.
A 40-year-old man is still missing.
Hery Purnomo was unable to say what type of ritual they performed but said the guru survived the tragedy and will be questioned.
Regional military commander Batara Pangaribuan told TVOne that the beach was usually guarded and closed after dark, but the group managed to enter.
Authorities had urged tourists not to swim or get too close to the water due to the risk of strong waves.
Last year, two Indonesian tourists died after being swept away by waves on a beach in Malang district, East Java.
In 2019, five people vacationing on a beach in Lampung province died after being swept away by a heavy swell.