The U.S. State Department released an additional 7,000 pages of heavily redacted emails from Hillary Clinton's time as the nation's top diplomat on Monday night.

The 4,300 messages were published in compliance with a court order that demanded the department reveal some of the former secretary's emails each month and make the full, 55,000-page cache available by Jan. 29, 2016, The Hill explained.

Observers paid close attention to the fact that 125 of the newly released emails have been flagged for containing classified information, an acknowledgement that could spell trouble for Clinton as the Democratic presidential candidate has admitted having used her private email account for government business during her time in Foggy Bottom.

But State Department spokesman Mark Toner insisted that the information redacted from Clinton's emails was not classified at the time but had been determined to contain sensitive material later on.

"The information we have upgraded today was not marked classified at the time the emails were sent. They have been subsequently upgraded," Toner explained. "It is routine to upgrade information to classified status during the (Freedom of Information Act). This happens frequently -- several times a month. We are identifying documents that need to be classified today prior to public release."

Meanwhile, NPR published a list of "highlights" from the latest batch of Clinton emails that included a completely redacted call sheet for a meeting with then-New York City Mayor Michael Bloomberg, as well as a suggestion that her department partner with the Clinton Foundation led by her husband, former President Bill Clinton.

A message dated June 26, 2010, also revealed the then-secretary was an early adopter of Apple's iPad, which had been released just a few months earlier.

"That is exciting news," Clinton wrote in a message apparently addressed to senior State Department adviser Philippe Reines. "Do you think you can teach me how to use it on the flight to Kyev next week?"