According to Britney's ex husband Kevin Federline, Jamie attacked the couple's son in August.
'The Ventura County Sheriff’s Office investigated allegations involving child abuse by Mr. Spears. After reviewing the evidence, there is insufficient proof that a criminal offense was committed by Mr. Spears,' Ventura County District Attorney Gregory D. Totten said in a statement.
Kevin obtained a restraining order following the incident and Britney is said to be 'furious' with her father and has not spoken to him since.
'Britney had the boys at Jamie’s condo on the evening of August 24. Jamie and Sean Preston got into an argument. Sean Preston felt unsafe and locked himself into a room. Jamie broke into the room and shook Sean Preston,' a source told UsWeekly.
'The whole incident was very upsetting to her and her boys. Kevin was and still is furious,' the source added.
Until this incident, Britney shared 50/50 custody of her sons yet since the alleged altercation her custody rights have been reduced to just 30 per cent.