A regional branch of the Japan Coast Guard has said that a Taiwanese research vessel was confirmed to have lowered what looked like a cable into waters in Japan's exclusive economic zone (EEZ) off Kagoshima Prefecture.

According to the 10th Regional Coast Guard Headquarters, based in the city of Kagoshima, a coast guard patrol boat spotted the Taiwanese vessel conducting the suspicious activity at a point some 335 kilometers west-northwest of the island of Tokunoshima in the prefecture around 3:50 p.m. Monday.

The JCG boat radioed the Taiwanese vessel and told it to stop the activity, warning that a survey without prior consent is not permitted. The Taiwanese ship passed the geographically equidistance line between Japan and Taiwan to the west at around 7:47 p.m. and left Japan's EEZ.

In June, the same Taiwanese vessel was found carrying out a survey without consent in Japan's EEZ near the southernmost prefecture of Okinawa, prompting the JCG to urge it to stop the activity.