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KYIV, Jan 17 (Reuters) - Ukraine's cyber police said on Monday that last week's hacking of government systems appeared to have destroyed "external information resources", suggesting the attack went beyond temporarily defacing government websites.
A cyber attack hit on Thursday and Friday warning Ukrainians to "be afraid and expect the worst" at a time when the country was bracing itself for a possible new military offensive from neighbouring Russia.
"It can already be argued that the attack is more complex than modifying the homepage of websites," the cyber police said in a statement, though adding that 95% of the sites affected were working again.
Ukrainian officials say the attack hit around 70 internet sites of government bodies including the security and defence council, the cabinet of ministers and several ministries.
"A number of external information resources were manually destroyed by the attackers," the cyber police said, without elaborating what these resources were.
A top security official on Saturday told Reuters the defacing of the websites was cover for more destructive actions behind the scenes, the consequences of which would be felt later. He did not elaborate at the time.
Ukraine believes Russia was ultimately behind the cyberattack though Serhiy Demedyuk, deputy secretary of the national security and defence council, said on Saturday that a group linked to Belarusian intelligence likely carried it out.
He also said the hackers used malware similar to that used by a group linked to Russian intelligence.
Russia and Belarus are traditional allies and have put on a united front in Moscow's standoff with the West over Ukraine. Belarus has not commented on the allegation it might have been involved in the hack, while Russia denied responsibility. (Reporting by Pavel Polityuk; Editing by Matthias Williams and Alex Richardson)
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