New York (CNN Business) Microsoft has been granted a court order to take over 50 websites it alleges were used by a North Korean hacking group to steal "highly sensitive information" from computers in the United States.

Microsoft MSFT filed a lawsuit in federal court on December 18 against two unnamed people involved in the group, known as Thallium, which is alleged to have used the websites to send phishing emails to break into users' accounts and gain access to their information. The suit was unsealed on December 27.

In some cases, court documents state Thallium impersonated Microsoft or made use of its brands, such as Office 365, to gain access to the accounts.

Shortly after the suit was filed federal district court Judge Liam O'Grady granted a temporary restraining order restricting Thallium from carrying out any further hacking of Microsoft or Microsoft customers. He also ordered the companies that host the 50 website domains Microsoft said were being used for hacking to hand control of those domains over to Microsoft.

The court will give representatives of Thallium the chance to appear on January 3 to argue against the decision becoming permanent, according to the order, though it is not clear whether any such representatives exist.

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