North Korean media appeared to ignore a new holiday established this year to celebrate the country’s nuclear missile development, as Pyongyang may remain cautious about promoting its most destructive weapons.

However, questions remain about how the holiday may have been celebrated internally, after state-run outlets made no mention of Rocket Industry Day on Nov. 29 or 30. South Korean military officials told reporters they did not detect any indications of a major event or celebration. 

The holiday was apparently created to mark the Nov. 29, 2017 test launch of the Hwasong-15 intercontinental ballistic missile (ICBM) — North Korea’s longest-range weapon