vessel caught fishing illegally in Taiwanese waters. The interdiction followed an increase in illegal fishing in Taiwanese waters by Chinese fishing vessels. Between January and July 2020 the CGA chased 2,988 Chinese sand dredging vessels out of Taiwanese waters. In July 2020 the CGA seized a dredging vessel and arrested its eight crew as a warning to the rest. In August 2020 the CGA detained a small Chinese oil tanker which had illegally entered Taiwan's waters. The oil tanker was discovered during enhanced COVID-19 pandemic biosecurity patrols. In May 2021 the CGA detained a Chinese offshore supply vessel and its 12 crew. The vessel was caught trespassing in Taiwanese waters near Penghu. It is believed that the supply ship was being used to deliver food and other supplies to offshore fishing fleets. In May 2022 an Anping-class patrol ship launched a Hsiung Feng II anti-ship missile for the first time in a joint exercise with the Navy. Intelligence Function Some people in Taiwan still regard the Coast Guard Administration as an intelligence agency due to its root. Indeed, the land branch of the Coast Guard Administration is inherited from the former Taiwan Garrison Command. As a result, a lot of intelligence personnel from the Military Police Command or the late Taiwan Garrison Command are still in the ROCCGA. There are several mobile investigative groups subordinated to four corresponding areas of responsibility of the Coastal Patrol Directorate General. All mobile investigative groups of the Coast Guard Administration are tasked to perform intelligence-gathering mission of State Security. While executing such intelligence-gathering function, The Coast Guard Administration is subjected to the supervisory and coordination from the National Security Bureau. International cooperation The CGA cooperates with Japan, the Philippines, Malaysia, Thailand, Indonesia, and Vietnam in operations to counter human trafficking and drug smuggling. The CGA and the Japan Coast Guard conduct annual exercises and visits. The CGA and the Philippines Coast Guard have conducted tabletop exercises and drills. The CGA and the US Coast Guard cooperate on monitoring longline fishing, maritime law enforcement, human trafficking, and drug smuggling. In 2010 the CGA held their first ever drill with China's Maritime Search and Rescue Center. The drill, which simulated a ferry disaster between Kinmen and Xiamen, included 14 vessels, 3 helicopters, and 400 personal. Due to the tense relations between the two countries participating forces used drill flags instead of their national flags and emblems.