The State Department says about 30 emails that may be related to the 2012 attack on U.S. compounds in Benghazi, Libya, are among the thousands of Hillary Clinton emails recovered during the FBI's recently closed investigation into her use of a private server.

Government lawyers told U.S. District Court Judge Amit P. Mehta Tuesday that an undetermined number of the emails among the 30 were not included in the 55,000 pages previously provided by Clinton.

The State Department's lawyer said it would need until the end of September to review the emails and redact potentially classified information before they are released.

Donald Trump's campaign lashed out, asking what else might be lurking among the emails Clinton ordered deleted.

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WEAKER? The State Department says about 30 emails that may be related to the 2012 attack in Benghazi, Libya are among the thousands of Hillary Clinton emails recovered during the FBI's recently closed investigation into her use of a private server

AFTERMATH: The inside of the U.S. consulate in Benghazi, Libya, after a deadly 2012 terror attack killed four Americans and gutted the facility while Hillary Clinton was secretary of state

'Today's disclosure that 30 additional emails about Benghazi were discovered on Hillary Clinton's private server raises additional questions about the more than 30,000 emails she deleted,' Trump campaign Senior Communications Advisor Jason Miller said in a statement.

'Hillary Clinton swore before a federal court and told the American people she handed over all of her work-related emails. If Clinton did not consider emails about something as important as Benghazi to be work-related, one has to wonder what is contained in the other emails she attempted to wipe from her server.'

The news about the new email discovery was first reported by The Washington Examiner.

During a March 2015 press conference at the United Nations after the existence of her homebrew, private email server was first made public, Clinton insisted that while she had ordered the deletion of more than 33,000 emails, all of them were personal in nature.

'We went through a thorough process to identify all of my work-related emails and deliver them to the State Department,' she told reporters.

'At the end, I chose not to keep my private personal emails – emails about planning Chelsea's wedding or my mother's funeral arrangements, condolence notes to friends as well as yoga routines, family vacations, the other things you typically find in inboxes.'

DID SHE LIE? Clinton said in a March 10, 2015 press conference that she decided to delete only personal emails – not work-related ones

Judge Mehta questioned why it would take so long to release so few documents, and urged that the process be sped up.

He ordered the department to report to him in a week with more details about why the review process would take a full month.

The hearing was held in one of several lawsuits filed by the conservative legal group Judicial Watch, which has sued over access to government records involving the Democratic presidential nominee.

The State Department has said the FBI provided it with about 14,900 emails purported not to have been among those previously released.

Clinton previously had said she withheld and deleted only personal emails not related to her duties as secretary of state.

With the November election little more than two months away, Republicans are pressing for the release of as many documents related to Clinton as possible.

In a separate development Tuesday, a law enforcement official told The Associated Press that the FBI is expected to release documents soon related to its investigation, which focused on whether Clinton and her aides mishandled government secrets.

The official, who wasn't authorized to discuss the matter by name and spoke on condition of anonymity, said documents in the case would be made public as the FBI responds to Freedom of Information Act requests.

It wasn't immediately clear when the documents would be released or exactly what they would include.

Though he described Clinton's actions as 'extremely careless,' FBI Director James Comey said his agents found no evidence that anyone intended to break the law and said 'no reasonable prosecutor' would have brought a criminal case.

The FBI this month provided Congress portions of its file from the agency's yearlong investigation.

The FBI interviewed Clinton for several hours at FBI headquarters in Washington just days before announcing its decision to close the investigation. The Justice Department accepted the FBI's recommendation.

Since the conclusion of the investigation the emails have continued to be a political problem for Clinton, as the exchanges have shown a cozy relationship between her State Department and the Clinton Foundation, which Trump has characterized as 'pay-for-play' in the past week.

While there has been no evidence suggesting that Clinton Foundation donors successfully pushed policy changes while Clinton served as President Obama's secretary of state, emails that the conservative watchdog Citizens United released this week show one of Clinton's top aides, Huma Abedin, alerting the foundation's people that Clinton would be off the grid during a trip to Russia.

'This is an email about their State Department travel on an official trip to Russia that Abedin is sending to the foundation, to they understand they would be off the grid,' Citizens United's David Bossie said. '"If you need anything call us." This is just part and parcel of what was going on.'

Bossie noted that the same set of emails also indicates that Clinton's aides were aware that her private email address was insecure, as Abedin said she wouldn't be using that address while traveling to Russia for fear of hacks.