Anyone who asks Vitaly Zushtchevski about the allegations being made against his former employer is quickly interrupted. "It is a lie," said the ex-deputy production manager for engines at Yuzhmash, the former Soviet rocket manufacturer based in the eastern Ukrainian city of Dnipro. According to a New York Times report published on Monday, North Korea's surprising progress in missile technology may be linked to Yuzhmash.

The engineering plant is in financial difficulty, and this may be the reason why criminals and former employees reportedly smuggled old Soviet engines, or parts of them, into North Korea. The Times referred to a study conducted by Michael Elleman from the International Institute for Strategic Studies (IISS) in London and assessments by US intelligence agencies. The newspaper did not provide evidence, only clues.

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Aiding a technological leap

Elleman has analyzed North Korean medium-range and intercontinental ballistic missiles of the Hwasong 12 and 14 types, whose extended range holds the potential to hit the United States. He concluded that the surprisingly fast development in the last two years has only been possible with the help of foreign suppliers, meaning countries from the former Soviet Union. Even the German missile expert Robert Schmucker from the Technical University of Munich (TUM) agreed with Elleman's analysis, although he avoided any explicit accusations.

Experts believe that the one-chamber engine used in the latest Hwasong missiles is reminiscent of the Soviet RD-250 rocket engine, which had two chambers and was developed in the 1960s.

It is difficult to prove whether the RD-250 was also manufactured by Yuzhmash. Vitaly Zushtchevski said that they received these engines from Russia, where they were "produced in low quantities." Elleman suggested that they were also made in Ukraine. In his IISS study, he wrote that "hundreds, if not more" RD-250 engines have remained in Russia, as well as in Ukraine, adding it is also possible that Moscow is Pyongyang's supplier.

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"We have never produced the types of engines that are shown in the New York Times article," said Zushtchevski, who worked at Yuzhmash for almost five decades. The retired engineer confirmed that since the end of the company's cooperation with Moscow, triggered by the annexation of Crimea, the rocket plant in Dnipro has been "virtually dead." Smuggling technology into North Korea is unfathomable to him. Kyiv and Yuzhmash officials both denied the Times report. Elleman suspects the government in Kyiv knew nothing about the smuggling.

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Shadow of the past

It is the first time that Yuzhmash, the former manufacturer of the giant Soviet SS-18 intercontinental ballistic missile, has been suspected of violating UN sanctions or any other international treaties. However, Pyongyang has shown its interest in Ukrainian expertise in the past. In 2012, two North Koreans were tried in Ukraine for spying on Yuzhmash.

In 2002, there were press reports claiming that Ukraine wanted to supply Iraq with modern radar systems. Kyiv denied the reports and no radar systems were found in Iraq. But there were cases of verified smuggling. In 2005, the then-prosecutor general of Ukraine admitted in a newspaper interview that a group of Ukrainians and Russians illegally sold 18 cruise missiles to China and Iran in 2001.

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Oleg Uruski, former head of the State Space Agency of Ukraine, finds it improbable that the same could have happened in this case, saying that the state has a multistage monitoring system. However, Uruski did not rule out that the clues point to wrongdoing. "A crime is possible in every sphere," he said.

Pointing the finger at Moscow

Observers in Kyiv believe that the Times article may be part of a targeted campaign by Russia. In an analysis published on Tuesday, the Center for Army, Conversion and Disarmament Studies (CACDS) in Kyiv wrote that the US publication shows "signs of an information attack on Ukraine." Among other things, the aim of the article is apparently to divert attention from "their own missile technology shipments to North Korea" and to discredit Ukraine, especially in the eyes of the US.

"Russia shares a border with North Korea, so one can deliver anything, even entire engines," said Mykhailo Samus, the CACDS deputy director for international affairs. Ukraine, on the other hand, would have logistical problems, he said.

TUM's Robert Schmucker said that the latest story is about more than just the engines. "What about the missiles? The information itself is of no use; you need production facilities, technical equipment and above all, good quality control," he said. "A lot more must have come from Ukraine than just a few engines."