China has carried out massive naval drills over the past 10 days in the West Sea and western coastal waters in an apparent attempt to counter joint South Korea-U.S. exercises in the East Sea.

South Korea and the U.S. staged the drill in response to North Korea's sinking of the South Korean Navy corvette Cheonan in March.

The aircraft carrier USS George Washington and its air wing take part in a joint maritime and air readiness exercise with South Korea in the East Sea on Wednesday, the last day of the drill. /Newsis

The South China Morning Post on Wednesday said the People's Liberation Army "conducted two more military drills in the Yellow [West] Sea region -- the second and third in 10 days."

The Chinese carried out a troop rescue and arms transport drill in the West Sea near Yantai, Shandong Province on July 17-18 involving a large number of ships and fighter jets. Next were drills in the Nanjing Military District of Jiangsu Province and in the Jinan Military District of Shandong Province, the Hong Kong newspaper said.

Experts said that it was unprecedented for the Chinese to stage three drills of this magnitude in these waters since it carried out almost none in the West Sea for decades.