Customs officials in the Indian state of Kerala have begun cracking down on local fishing boats fitted with AIS transponders that were manufactured in China.
The move comes after a number of local agencies reported that many of the transponders have been sending out erroneous vessel locations and MMSI numbers.
A recent investigation by the Indian Coast Guard and state fisheries officials revealed that some Kerala fishing boats fitted with Chinese AIS had MMSI numbers that were already being used by Chinese-registered vessels.
A customs official warned that AIS transponders sending out incorrect data posed "a threat to national security" as these devices would make the task of tracking smuggling activities in the country's waters even more difficult.
The Kerala government said that the proliferation of the Chinese AIS devices was partly due to their affordability, with each one typically costing only a sixth of the price of a standard locally-issued transponder.