North Korea conducted a simulated “scorched-earth” nuclear strike on targets across South Korea, state media reported on Thursday, in reaction to allied exercises that it said amounted to plans for a preemptive nuclear attack by the US.

“The KPA staged a tactical nuclear strike drill simulating scorched-earth strikes at major command centers and operational airfields of the ‘ROK’ military gangsters on Wednesday night,” the general staff of the North’s Korean People’s Army (KPA) said in a statement carried by the KCNA news agency. ROK is the initials of South Korea’s official name, the Republic of Korea.

North Korea fired two short-range ballistic missiles into the sea on Wednesday, South Korea’s military said, hours after the US deployed B-1B bombers for allied air drills.

“These conducts pose threats to the peace and stability of not only our country but of the region and international community and cannot be tolerated,” Japanese Prime Minister Fumio Kishida told reporters.

The launches late Wednesday came a day before South Korea and the US were set to wrap up 11 days of combined military drills, which North Korea has long denounced as a war rehearsal.

North Korean leader Kim Jong Un observed on Tuesday part of a drill that involved the commanding officers and staff sections of the entire army and was aimed at preparing them for an all-out war with the South, KCNA reported.