TAIPEI (Taiwan News) – Taiwan tracked four Chinese coast guard vessels approaching a restricted area south of Kinmen on Friday (Sept. 13).

The Coast Guard Administration (CGA) unit responsible for Kinmen, Matsu, and Penghu immediately sent four patrol vessels to order the Chinese to leave, per CNA. It was the 39th such incident near Kinmen this year, the CGA said.

All four Chinese ships appeared at the same time around 8:50 a.m., leading the CGA to send in the same number of vessels to shadow each Chinese ship. The CGA broadcast warnings in Mandarin and English before the Chinese coast guard vessels left at 11 a.m.

The incident was the first of its kind in September, though Chinese coast guard ships have intruded into restricted waters near Kinmen frequently since early this year. China claims it has the right to patrol the waters around Taiwan-held islands close to the province of Fujian.

In separate incidents near Kinmen, two Chinese fishers died when their unregistered speedboat was chased by the CGA in February, while China detained two Taiwanese fishers as they strayed into Chinese waters during poor weather in March.