The two "top secret" emails found by investigators on Hillary Clinton's unsecured private email system include discussion of a news article about a U.S. drone operation, the Associated Press reported Friday.

The article references classified information, and one of Clinton's advisers followed up "in a way that could possibly be inferred as confirmation," U.S. officials said.

"The drone exchange, the officials said, begins with a copy of a news article that discusses the CIA drone program that targets terrorists in Pakistan and elsewhere," AP wrote. "While a secret program, it is well-known and often reported on. The copy makes reference to classified information, and a Clinton adviser follows up by dancing around a top secret in a way that could possibly be inferred as confirmation, they said. Several officials, however, described this claim as tenuous."

A separate conversation found in the emails could point back to highly classified information in an improper manner, or simply reflect data information collected independently, U.S. officials said.

The AP said the two emails about drones were marked classified after consultations with the CIA, which is where the classified information originated.

The officials, who work in intelligences and other agencies, spoke to AP on condition of anonymity and wouldn't detail the contents of the emails due to the ongoing concerns over classification levels. They said that Clinton did not transmit the sensitive information herself.

Clinton, now the Democratic presidential front-runner, has faced significant scrutiny for deciding to forgo the usual government email system during her time as secretary of state and instead set up her own private email server and address, which was not secure enough to handle classified information. The FBI has opened a criminal probe into Clinton to see what kind of information passed through her server, fearing that foreign governments and hackers may have infiltrated it and stolen highly sensitive information.

Clinton finally turned over the private server to Justice Department investigators earlier this week after refusing to do so for months, as HNGN reported.

Hours before, on Monday, the inspector general for the 17 spy agencies told Congress that they examined a random sample of 40 emails from the 30,000 Clinton gave the State Department for record-keeping purposes and found that two emails contained information considered to be "Top Secret/Sensitive Compartmented Information," which is one of the government's highest levels of classification.

Clinton unilaterally deleted another 30,000 emails after deeming personal in nature, and then wiped the server clean.

"The developments suggested that the security of Clinton's email setup and how she guarded the nation's secrets will remain relevant campaign topics," AP said. "Even if the emails highlighted by the intelligence community prove innocuous, she will still face questions about whether she set up the private server with the aim of avoiding scrutiny, whether emails she deleted because she said they were personal were actually work-related, and whether she appropriately shielded such emails from possible foreign spies and hackers."

Clinton continues to insist that she did not personally send or receive any emails with classified information.