Most of Ukraine's government sites back online after "massive" cyberattack

• Russia has amassed more than 100,000 troops on the border with Ukraine, raising fears that Russian President Vladimir Putin could invade in an attempt to stop Ukraine from strengthening its ties with the West.
• "Ukrainian! All your personal data was uploaded to the public network. All data on the computer is destroyed, it is impossible to restore it," a message written on the hacked websites said, according to Reuters.
• The note, written in Ukrainian, Russian and Polish, added: "All information about you has become public, be afraid and expect the worst. This is for your past, present and future."

What they're saying: "As a result of a massive cyber attack, the websites of the Ministry of Foreign Affairs and a number of other government agencies are temporarily down," Foreign Ministry spokesperson Oleg Nikolenko said on his official Twitter account Friday morning.

• "Our specialists have already started restoring the work of IT systems, and the cyberpolice has opened an investigation," Nikolenko added.

The big picture: NATO secretary general Jens Stoltenberg said in a statement Friday that the organization's cyber experts and Ukraine are sharing information on the cyber activities against the governmental websites.

• "In the coming days, NATO and Ukraine will sign an agreement on enhanced cyber cooperation, including Ukrainian access to NATO’s malware information sharing platform," Stoltenberg added. "NATO’s strong political and practical support for Ukraine will continue."

Go deeper: Russian officials to brief Putin on "very disappointing" security talks

Editor's note: This article has been updated with comments from Andriy Yermak.