North Korea’s recent flurry of missile launches — including one of a “new” weapon that overflew Japan — simulated strikes with smaller “tactical” nuclear warheads designed for use on the battlefield, the latest signal that Pyongyang is preparing for its first atomic test since 2017.

Leader Kim Jong Un oversaw the military exercises that ran from Sept. 25 through Sunday and involved loading mock nuclear warheads on missiles, the official Korean Central News Agency (KCNA) reported Monday.

Seven launches, in which 12 missiles were fired, simulated the targeting of military command sites, striking main ports and hitting airports in the South, with Pyongyang seeking to assess its “war deterrent and nuclear counterattack capability.”