After compromising Microsoft's official blog and one of its Twitter accounts last month, the Syrian Electronic Army sifted through employees' emails to acquire documents related to law enforcement inquiries.
The company is investigating the information breach, but does not plan to release any of the documents' details, according to a Microsoft blog post.
In addition to stealing email content, the hacker collective defaced the company's blog with posts announcing the SEA's presence.
The hacker collective also tweeted, “Don't use Microsoft emails (hotmail,outlook), They are monitoring your accounts and selling the data to the governments,” to the @MSFTnews Twitter account earlier this month.
In its 2013 transparency report, Microsoft said it received 37,916 requests from law enforcement agencies that could have impacted more than 66,000 user accounts.