Police are unable to determine how pages of the Nashville mass shooter's manifesto leaked last month following an inconclusive investigation.

Metro Nashville Police Department said in an email Friday that investigators have "exhausted all available investigative avenues" searching for the individuals responsible in leaking portions of mass murderer Audrey Hale's manifesto. 

Investigators determined two officers in the Specialized Investigations Division who discovered Hale's manifesto in her automobile near the scene of the crime had taken pictures of the handwritten document. 

NASHVILLE POLICE SAY 7 ON ADMIN ASSIGNMENT AFTER PURPORTED LEAK OF CHRISTIAN SCHOOL SHOOTER'S MANIFESTO

Covenant Church Nashville

Two women hug near a memorial at the entrance to The Covenant School in Nashville, Tennessee. Nashville Police have "exhausted all available investigative avenues" in the hunt for the person who leaked pages from a school shooter’s journals to a conservative commentator, the department announced in an email sent to media. (AP Photo/Wade Payne)

Seven Nashville officers were also transferred to administrative positions following the leak of the manifesto.

However, investigators say they were unable to pin down the individual responsible for handing over portions of the manifesto to conservative entertainer Steven Crowder, who published the photos on Nov. 6.

"The department does not have the ability to compel statements or cooperation from former employees," the police department said in a statement.

NASHVILLE POLICE WHO RESPONDED TO COVENANT SCHOOL SHOOTING HONORED IN STEVE PENLEY PORTRAIT

All officers ultimately returned to their regular positions.

Court documents earlier this year revealed Hale, whom Nashville police describe as a transgender woman, had over 20 journals.

The killer's writings have been the source of intense controversy after lawsuits were filed to force the release of the texts. 

Nashville Tennessee Covenant Shooting

An entrance to The Covenant School is seen in Nashville, Tennessee.  ((AP Photo/George Walker IV, File))

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Simultaneously, some of the school's parents have moved to block the release of the manifesto, claiming it would further endanger the student body or inspire copycat killers.

The lawsuit has been slowed for months. Currently, an appeals court is expected to rule on whether Hale’s parents and the school have a right to intervene. There is no clear timeline for a decision on releasing the full manifesto.

Fox News Digital's Michael Ruiz, Adam Sabes, and Samantha Daigle contributed to this report.