South Korea’s military says it has detected North Korea firing multiple cruise missiles into waters off its northeastern coast in its fifth test of such weapons since January.

South Korea’s Joint Chiefs of Staff on Wednesday didn’t immediately provide the exact numbers of missiles fired or how far they flew. It added that both South Korea and U.S. intelligence agencies were “conducting a detailed analysis.”

The launches were North Korea’s sixth missile-launch event this year, also including a Jan. 14 test of the country’s first solid-fuel intermediate-range missile.

Tensions on the Korean Peninsula are at their highest point in years after North Korean leader Kim Jong Un accelerated his weapons demonstrations to a record pace and issued provocative threats of nuclear conflict with South Korea and the United States.