North Korea test-fired a new ballistic missile carrying a super-large warhead and an improved strategic cruise missile, state media reported Thursday, as leader Kim Jong Un called for increased weapons development.

North Korea fired multiple short-range ballistic missiles on Wednesday toward its east coast, South Korea and Japan said, days after Pyongyang unveiled a uranium enrichment facility and vowed to beef up its nuclear arsenal.

South Korea’s Joint Chiefs of Staff said it detected North Korea firing multiple short-range ballistic missiles from north of its capital, Pyongyang, and said they traveled about 400 kilometers (244 miles) while flying toward the northeast.