By Olga Pavlova and Nathan Hodge, CNN
(CNN) -- The Kremlin broke its silence Tuesday on the apparent explosion of a nuclear-powered cruise missile during a test, saying that accidents "happen" but that Russia remained "far ahead" in the development of advanced weaponry.
Kremlin spokesman Dmitry Peskov declined to confirm widespread international speculation that the accident -- which claimed the lives of at least five nuclear specialists last Thursday -- involved a nuclear-powered cruise missile known as the Burevestnik or Skyfall.
But in a conference call with reporters, Peskov denied that such mishaps would set back Russian efforts to develop advanced military capabilities.
The spokesperson said that only experts could speak with authority on such matters, but added: "Accidents, unfortunately, happen. They are tragedies. But in this particular case, it is important for us to remember those heroes who lost their lives in this accident."
Peskov then repeated an assertion by President Vladimir Putin that Russian efforts to develop such technologies remained "considerably far ahead of the level other countries have managed to achieve."
He also responded to a tweet by President Donald Trump, who said the US was "learning much from the failed missile explosion" and claimed that America has similar, but more advanced, technology.
"It would certainly would be quite strange if a country -- a world superpower that spends more money on defense than all the rest of the countries of the world -- was not involved in such projects," Peskov said, when asked to respond to Trump's statement. "That is why is this is not new information."
Rosatom, Russia's state atomic energy company, confirmed that five of its nuclear specialists were killed in the incident. The total casualty count is still unclear.
Local authorities reported a brief spike in radiation following the incident, while Russia's Defense Ministry said radiation levels were normal.
Asked to comment on the conflicting reports and concerns about the consequences for the local population, Peskov said: "I have nothing to add beyond what I stated. ... I can just assure you that in such a situation all the competent agencies do everything to assure the safety of the citizens of the Russian Federation is fully provided."