Hillary Clinton seemed to greet a supporters while campaigning in the state of Iowa, Friday, 01/29/2016.
As many as 22 emails sent through the server Hillary Clinton his home when he was a United States Secretary of State to contain state secrets, US officials said.
Spokesman for the US State Department, John Kirby, said the e-mails are not marked as confidential messages when delivered.
In fact, according to the US State Department, the message was a "confidential matter" and could not be released.
Sensitive informationHillary Clinton, who sought the nomination of the Democratic Party in the presidential election this year, has previously been criticized for using a personal computer server to send emails while still serving his job.
Based on the request, thousands of emails were released by the US State Department. But this is the first time email messages classified as secret.
Clinton campaign team upset over the announcement and demanded that the emails were made public in full.
Email messages are marked as "confidential matter" because it can cause a "great danger" to national security if revealed, the State Department said.