The hunt for doomed Malaysia Airlines flight MH370 is likely to be the most expensive in aviation history, Chinese scientists warned yesterday, as Thailand said it had spotted hundreds of objects near the search area in the Indian Ocean.

The annual bill could run to 10 times that of the two-year hunt for an Air France plane five years ago and would cost hundreds of millions of US dollars, they said.

France and Brazil spent more than US$40 million over two years to recover the black boxes from Air France flight 447, which crashed in the Atlantic Ocean in 2009 en route to Rio de Janeiro from Paris. Officials halted the operation, which used underwater robots to scour the seabed, after search crews found 50 of the 228 bodies.

… No international protocol exists to assign or split accident investigation costs. Oh Ei Sun, of the S. Rajaratnam School of International Studies in Singapore, said that in theory, the lead investigating nation should pay.