They occured in the National Violence Reduction Unit.
Three members of staff at the Midlands Prison have been injured, after two incidents in the last week.
One staff member was head-butted by a prisoner last Thursday; while on Tuesday, two officers were injured in an incident and taken to A&E.
The Irish Prison Service says the incidents - which happened in the National Violence Reduction Unit - have been referred to the gardaí.
The unit engages with the prison's most violent inmates - with an emphasis placed on psychological rehabilitation.