North Korea tested a rocket engine for the third time this month — and like the previous two tests, it showed signs the rogue nation’s missile capabilities were improving, a U.S. official confirmed Tuesday to Fox News.

None of the three rocket tests ended in an embarrassing explosion, showing the secretive regime has made progress, the official said. The test did not demonstrate any new capabilities.

The Pentagon continues to see signs North Korea is edging closer to conducting another nuclear test, following two successful tests last year.

North Korea conducted the latest test last Friday night, Reuters reported, adding that Kim Jong Un’s regime could use the engine in an intercontinental ballistic missile, or ICBM.