TAIPEI (Taiwan News) — The Coast Guard confirmed Sunday that a Chinese vessel circled Taiwan and that it monitored the vessel by radar throughout its journey.

The Facebook page Taiwan ADIZ posted a graphic showing the path of Lian He Hai Gong 5001 during a PLA joint combat readiness patrol questioning what it was towing, per UDN. The Coast Guard said it began radar surveillance when the vessel entered nearby waters and dispatched patrol ships to issue radio warnings and ensure maritime security.

Radar monitoring showed the vessel did not anchor or conduct any underwater operations during its voyage. No damage or abnormalities involving submarine cables were detected.

The Coast Guard said it will continue strengthening maritime surveillance and respond under the law to any threatening actions by Chinese vessels. It said that safeguarding Taiwan’s maritime security is its core mission.

To deal with future similar incidents, the Coast Guard said it will coordinate with the National Security Council, the Ministry of National Defense, and other agencies to enhance awareness and protect national security.