Hillary Clinton has said she cannot recall key details about using a private email server while secretary of state.

The Democratic presidential runner had been asked to give sworn responses to 25 written questions from the Judicial Watch group.

According to the documents provided by Hillary Clinton’s lawyer, at least 21 responses used variations of “does not recall”.

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Hillary Clinton denies handling classified information in her private emails.

Questions over her use of a private email server while secretary of state have dogged her presidential campaign.

Hillary Clinton’ responses under oath to the Judicial Watch group were provided by her lawyer, David Kendall.

She also made various legal objections to the wording or formation of 18 of the 25 questions, the documents show.

Correspondents say Hillary Clinton’s answers provide no new information beyond what she told FBI agents during a recent investigation.

Judicial Watch President Tom Fitton said the group’s lawyers would be closely reviewing her responses.

“Mrs. Clinton’s refusal to answer many of the questions in a clear and straightforward manner further reflects disdain for the rule of law,” he said.

Judicial Watch has filed multiple lawsuits to try to obtain copies of government documents from Hillary Clinton’s time as secretary of state.