A Chinese spy ship was spotted lurking off the Australian coast for three weeks and passing several major military bases. The Dongdiao-class spy ship entered the 200km exclusive economic zone off the coast of Darwin in August. The ships are equipped with sophisticated antennas and radar technology that allows them to monitor defences. China has used them to spy on Taiwan . The vessel ventured south and traveled along the east coast before passing 'one of Australia's prime military training areas' in Shoalwater Bay, Queensland . A Chinese spy ship was spotted lurking off the Australian coast for three weeks…