South Korea alleged that the DPRK launched a cyber attack targeting a joint military drill with the United States that is scheduled to start on Monday.

The two allies will begin their annual exercise dubbed "Ulchi Freedom Shield," a ten-day event that is directed against Pyongyang in particular, and other US adversaries in East Asia in general, on top of which is China.

A joint probe between the US Army and the Gyeonggi Nambu Provincial Police Agency claimed that DPRK hackers carried out "continuous malicious email attacks" on South Korean military contractors operating at the joint war simulation center linked to the exercise.

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"Police investigation confirms that North Korean hacking group was responsible for the attack," the police said in a statement, adding that no information was compromised.

The report claimed that a group that goes by the name Kimsuky was suspected of being responsible for the infiltration, citing a similar tactic used in 2014 against Seoul's nuclear reactor.

Since March, the US and South Korea have undertaken large-scale joint military drills, simulating large-scale bombing against the DPRK.

Pyongyang has consistently denounced the joint exercises of the allies as rehearsals for invasion while cautioning about the repercussions of sustained hostility led by Washington in the region.

The head of the DPRK Kim Jong Un called last week for increased preparations for the potential of war, boosting weapon manufacturing and extending military exercises.

His remarks followed a visit to a weapons factory when he demanded the production of more artillery, missile engines, and other armaments.

Responding to the increasing provocations, including raising nuclear tensions, the DPRK warned earlier this month the US and its allies against their "dangerous war games," which "may incite an unprecedented nuclear war in the Korean peninsula."

"If the United States of America attempts to use armed forces against the Democratic People's Republic of Korea, the former will face an unimaginable and unforeseen crisis," the country's National Defense Minister said then.