SEOUL, May 23 (Xinhua) -- An unidentified flying object from the Democratic People's Republic of Korea (DPRK) crossed an eastern border with South Korea Tuesday afternoon, Seoul's military said.

The South Korean military detected an unidentified projectile crossing the military demarcation line in Cheorwon, Gangwon province at about 4 p.m. local time (0700 GMT), according to the Joint Chiefs of Staff (JCS).

The Seoul military conducted a warning broadcast and fired warning shots toward the flying object in accordance with proper procedures, the JCS said in a statement.

The flying object returned back to the DPRK, and the South Korean military was analyzing the projectile.

The statement said the military strengthened its air observation and maintained defense readiness.