It is a bizarre new twist in a police probe into allegations the World Cup winner was targeted by extortionists.
More than 30 videos of Mathias Pogba reading to camera in French from a lengthy statement were posted to Twitter on Friday.
It is not clear exactly when the clips were filmed, but it may have been before Mathias turned himself in for police questioning last week.
He has reportedly been in custody since.
Recording the video appears to have been time consuming – he wears three different T-shirts.
“If you are watching this video that will be because my brother Paul Pogba has found a way to silence me,” he said in the first of the series.
“I record this video so that whatever happens, everything is revealed.”
The words “insurance video, held in a safe place” are written on top of many of the videos.
They followed through on previous social media posts where Mathias threatened to make explosive revelations about his brother, who now plays for Juventus.
Mathias and four others were hit with preliminary charges last Saturday and jailed in the extortion probe, French prosecutors said.
In the latest series of recordings, Mathias accuses his multi-millionaire brother of having abandoned members of their family, leaving them in poverty.
He also claims the midfielder mixed with criminals and repeats claims the 29-year-old midfielder employed a witch doctor.
The videos were accompanied by a series of Twitter posts and a statement addressed to Pogba.
The first post in the long thread said it had been sent automatically by “my bot”.
“That also means that I am no longer free,” the message read.