BEIJING, Dec. 18 (UPI) -- China staged a military exercise involving submarines and fighter jets in the South China Sea, one of the busiest maritime trade routes in the world.
The drill took place on Wednesday and included the deployment of submarines, battleships, early warning aircraft and fighter jets, China's Liberation Army Daily reported Friday.
The objective of the training was to simulate a response to a cruise missile attack, South Korean news agency Yonhap reported.
Thousands of Chinese troops, divided into blue and red teams, were deployed in the training exercise in a large area in the South China Sea.
The simulation included responses to scenarios of a missile attack on a commercial vessel, according to Chinese state media.
An estimated $5 trillion of goods travel through the maritime zone, and China recently has continued land reclamation activities on disputed reefs in the Spratly Islands, also claimed by the Philippines, Vietnam, Taiwan and Brunei.
The United States, a non-claimant, has criticized China's activities, and in November a U.S. B-52 strategic bomber flew over the man-made islands.
In October, a U.S. Navy destroyer, the USS Lassen, sailed within 12 nautical miles of the Subi Reefs, prompting Chinese patrol boats to issue a warning.
China also has begun stepping up ways to reach military buyers outside its region.
The New York Times reported Thursday that the China-made Caihong-4, an unmanned aerial vehicle, was exported to Baghdad, joining U.S.-made drones in Iraq, where large parts of territory are under threat of strikes from the Islamic State.
"This is the first time I've heard of a Chinese drone, such as the CH-4...I suppose it would be cliché to say that it won't be the last," said Richard A. Bitzinger, a senior fellow at the S. Rajaratnam School of International Studies at Nanyang Technological University in Singapore.