Over 900 earthquakes hit Japan's Tokara Islands within 2 weeks, authorities don't know why

Over 900 earthquakes have struck an island chain in southern Japan within the past two weeks, including a magnitude-5.5 quake on Jul. 2.

While there have been no reports of damage or tsunami warnings yet,  residents in the Tokara Islands have been left sleep-deprived from the quakes and anxiety.

They have also been advised by the authorities to prepare for evacuation if the need arises, BBC reported.

The tremors, which began on Jun. 21, have been occurring at a frequency nearly three times as much as in similar past events.

But the cause is still unclear.

"Unfortunately, we still don't know why it is happening or what will happen in the future," an official from the Japan Meteorological Agency told The Japan Times.

911 earthquakes have been recorded as of late afternoon on Jun. 2.

No more tourists

Due to the quakes, some guesthouses on the Tokara islands have stopped accepting tourists.

The guesthouses may be used as shelters for locals in the event of a disaster.

Authorities also urged the media to stop inundating locals with queries.

"We ask that you be considerate and not make excessive inquires or interviews," read a notice on the Toshima Village website.

The string of tremors comes on the back of rumours that a once-in-a-century megaquake could soon hit Japan.

Previously, the Japanese government issued a prediction that an earthquake with a magnitude of 8.8 could hit Japan, with a death toll as high as 298,000.

A 1999 manga, predicting a disaster in July 2025, also recently went viral.

Titled "The Future I saw", the novel previously warned of a major disaster in March 2011.

The date coincided with a 9.0-magnitude quake that devastated northeastern Japan.

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