Qatar has denied the allegations, but the development has raised concerns in India, especially Kerala.
"There are about 6.5 lakh Indians in Qatar, of which nearly three lakh people hail from Kerala, and I bring to your attention our concern regarding their safety and future of their employment and their engagement in Qatar," Mr Vijayan wrote.
"Millions of Indians are working in countries in the Middle East and therefore the geo-political developments in the region has raised deep concerns among the people in the state, since each family has at least one family member or a relative in the region," Mr Vijayan wrote.
The Gulf states have banned their citizens from travelling to Qatar and ordered Qatari citizens to leave within a fortnight. Saudi Arabia also sealed its borders with Qatar, blocking the supply lines for food that go by land.
The measures taken against Qatar by the Gulf nations are severe. In 2014, Saudi Arabia, Bahrain and the UAE had withdrawn their ambassadors from Doha to register protest.
Read Kerala Chief Minister Pinarayi Vijayan's full letter here:
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