Chinese Maritime Safety Administration, or MSA, maritime law enforcement vessels in the waters east of Taiwan broadcast messages to three Taiwanese commercial vessels on June 7 and 9 inquiring about their origin and destination and asserting China's sovereignty over the waters, according to Taiwan's Coast Guard Administration, or CGA, on June 9. The CGA added that it instructed the three Taiwanese vessels to ignore the MSA requests, which they did, and the CGA responded to the MSA vessels by asserting Taiwan's sovereignty.