A report filed with a U.S. federal judge says a review of the emails of former secretary of state Hillary Clinton has found that as many as 305 of them could contain classified information.
The State Department filed the report Monday following a review by intelligence officials assigned to analyze the emails from Clinton's private server, which she used to send and receive messages during her tenure as secretary of state. Clinton is now the front-runner for the Democratic Party nomination for president.
The agency said the 305 emails with potentially classified data account for about 5 percent of the messages analyzed so far.
A lawsuit was filed against the State Department forcing it to review the emails on Clinton's private server. Those found to possibly contain classified information will be recommended to other federal agencies for further evaluation.
Clinton has insisted she never sent any information that was classified, and that she never received any information from others that was marked classified at the time.
The former secretary turned over her private email server last week. She has been pressured by Republican lawmakers to relinquish the server ever since it was revealed in March that she used her personal email account to send official messages. Critics have accused her of trying to hide controversial communications in her private account, including those concerning the deadly terrorist attack on the U.S. consulate in Benghazi, Libya in 2012.
Clinton has said she has turned over 55,000 pages of emails to the State Department and has authorized the agency to make them public.
The FBI has launched an investigation into the security of Clinton's private email server after the inspector general of the U.S. intelligence community said he found at least four emails that were classified at the time they were sent, including two that were deemed to be "top secret," the government's highest classification level.
Her campaign spokesman, Nick Merrill, has said Clinton has pledged to cooperate with the government's security inquiry, and if there are more questions, they will be addressed.