The first wave of a massive exercise to repatriate hundreds of thousands of Indians stuck abroad began on Thursday, with two flights landing in India from the United Arab Emirates, AFP reported.

Some 15,000 nationals will be repatriated from 12 countries on planes and naval ships, in a mammoth exercise which saw the civil aviation ministry's website crash on Wednesday as panicked citizens rushed to register.

Two warships have steamed to the Maldives and another to the UAE — home to a 3.3-million-strong Indian community which makes up some 30 per cent of the Gulf state's population.