A Chinese spy ship shadowed a U.S. aircraft carrier that was joining Japan and India in drills close to waters that China has laid claim to in the western Pacific Ocean.

Reuters reported, citing a Japanese official, that the USS John C. Stennis joined nine other naval ships, a Japanese military helicopter and Indian frigates in waters off of the Japanese Okinawan island chain. Submarine hunting patrol planes also joined in the annual exercise.

The official told Reuters the USS Stennis plans to break away from the other ships to act as a “decoy” to try and draw the spy ship from the naval exercises.

The latest show of American might comes as Japan and the U.S. worry about China extending its influence into the Western Pacific as it pushes its territorial claims in the South China Sea.

However, China has some troubles extending its reach across the entire Western Pacific. There are 200 islands that stretch through the East China Sea within 60 miles of Taiwan. Japan is reportedly fortifying those islands with radar stations to counter China’s influence.

Japan hopes that joining the U.S. in drills in the Pacific will deter Beijing’s growing power, while the U.S. Navy’s Third Fleet plans to work alongside Japan in the East Asia Sea, an official told Reuters Tuesday.

India, on the other hand, plans to use the drills to show its displeasure with China’s moves in the Indian Ocean. Four naval ships from India plan to tour the South China Sea and make stops in the Philippines and Vietnam.

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