PYONGYANG—In what appeared to be a more modest escalation of threats against the United States and its allies in the region, North Korea announced Thursday it had tested out a new knife, conducting a series of trial cuts with the weapon that state media described as “a great success.” “The Democratic People’s Republic of Korea has completed the development of a powerful new blade capable of traveling an entire arm’s length,” read a report from the Korean Central News Agency issued hours after U.S. satellite imagery confirmed researchers in a remote mountain region of the country had repeatedly thrown the knife end over end in an attempt to see if they could get it to stick in a tree trunk. “This weapon is capable of being waved around in a slashing motion within a one-meter radius of whoever holds it, and it can travel even farther when flung really hard. The DPRK will not be deterred in its pursuit of such technology by the American hypocrites, who possess hundreds, if not thousands, of knives.” Despite its bellicose tone, U.N. officials estimate North Korea is still three to four years away from developing a whetstone capable of honing the knife to the level of sharpness necessary to pierce human skin.