Former Gov. John Baldacci speaks during an at Abraham Lincoln School in Bangor, April 9, 2015.

Many documents from the administrations of Maine independent Gov. Angus King and Democratic Gov. John Baldacci have been deleted from state file servers — and are likely gone forever.

The Portland Press Herald reports that most of the document purges took place before the 2005 creation of the Office of Information Technology.

State Archivist Dave Cheever says officials transferred emails and documents to backup devices as part of routine purges to free up disk space. They didn’t realize many should have been retained and transferred to the state archives.

Some of the documents could be backed up on magnetic tapes. But those cannot be searched by keywords and become unstable over time.

Cheever said it’s unknown how many documents vanished. That’s because there are no records of what was deleted.