A case has been opened against the owner of the firearm that was found next to the body of co-author of The Lost Boys of Bird Island Mark Minnie, who police believe shot himself in a suicide earlier this month.
Police were investigating whether the owner had been negligent in safekeeping his firearm, Captain Priscilla Naidu told News24 on Monday.
No charges had been laid, she said.
The owner is a friend and former police colleague of Minnie.
READ: Mark Minnie's suicide note: 'Don't give up, Chrissy'
In terms of the Firearms Control Act, owners and dealers must abide by strict rules to keep their firearms safe.
It is an offence for people to not lock their firearm in a safe, strong room or safekeeping device when they are not carrying it, or it is not under their direct control.
Owners and dealers have to take reasonable steps to prevent their firearms from being lost or stolen, and keep the keys to their safe, strong room or device in safe custody.
Fifty-eight-year-old Minnie was found on the friend's smallholding in Theescombe on August 14.
READ: Mark Minnie's death was 'definitely not a suicide' - family member
He had a gunshot wound to the head and the firearm was next to his body. An apparent suicide note was found at the scene.
Naidu said the case remained an inquest and they did not suspect any foul play.
News24 previously reported that blood samples were taken and gun residue tests on Minnie's hands were done before they were sent to a forensics laboratory in Cape Town for testing.
In a suicide note to journalist Chris Steyn, who co-authored the book, Minnie said: "Chrissy, don't give up now. You are almost home."
In the note, Minnie also said he was tired and looking forward to "eternal rest".
The book alleges that former defence minister Magnus Malan, along with two other apartheid ministers and a local businessman, abused children on Bird Island, just off Port Elizabeth.
Both Minnie and Steyn had been investigating several leads that have cropped up since the book was launched but had been careful to not publicise what they had since unearthed.
According to a relative of Minnie, the family does not believe he committed suicide and believe the suicide note found at the scene was staged.
"This supposed suicide note was either written under duress, and I would like to see it before I will believe that it was written by Mark," relative Tersia Dodo recently told the SABC in an interview.
Dodo also told the SABC that the things Minnie had been exposed to, as a result of being involved with the investigation surrounding the book, had "really plagued him".
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