SEOUL, Aug. 30 (UPI) -- An annual 12-day joint military drill between the United States and South Korea was completed Friday, official said.

About 56,000 South Korean troops and 30,000 U.S. soldiers participated in the computer-aided exercises to test and improve their defense posture against the North, Yonhap News Agency reported.

"This year's Ulchi Freedom Guardian exercise further strengthened our combined defense and enhanced the readiness of the Republic of Korea, U.S. Forces and the U.N. sending states," Gen. James Thurman, the Combined Forces commander, said in a statement. "The exercise was based on realistic scenarios that enabled us to provide valuable training on our essential tasks and ensured we are fully prepared to defend the Republic of Korea."