Los Angeles , California ( CNN ) -- The judge overseeing the Mel Gibson child custody case ordered a probe into the leak of sealed court documents published on celebrity news website TMZ , a lawyer in the case said . The confidential documents `` were stolen probably from the court '' and the leaker `` got paid a good deal of money , '' said Martin Garbus , an attorney for Gibson 's ex-girlfriend , Oksana Grigorieva . Grigorieva and Garbus discussed the leaks in an interview scheduled to air Wednesday night on CNN 's `` Larry King Live . '' `` It 's medical documents , declarations , court opinions , transcripts , everything it seems , '' Garbus told King . TMZ has published sworn statements from Gibson , Grigorieva and another witness in the court fight over custody of 1-year-old Lucia . `` They say over 2,000 pages of documents were leaked and the district attorney 's office has started an investigation , '' Garbus said . A spokewoman for the Los Angeles district attorney said Tuesday that she was not aware of an investigation . TMZ 's spokeswoman declined to comment on the report of the investigation or the source of the documents . Lawyers involved in the case had copies , but Garbus suggested the leaked papers likely `` came out of the courthouse . '' `` Whoever took the files from the courthouse -- it 's 2,000 pages -- certainly got paid a good deal of money , '' Garbus said . The judge ordered the probe on Friday , Garbus said . A lawyer for Gibson declined to comment , but a publicist for Grigorieva said the leaks did not come from her side . `` It could be quite terrible because this case could turn into a gossip story , and swayed from what 's important here , '' Grigorieva said . `` It 's domestic violence and Lucia at stake . '' She has accused Gibson of domestic violence during their breakup earlier this year , while he accused her of extorting him with tapes she secretly made of their arguments . The Los Angeles County Sheriff 's Department is investigating both accusations . In another development , Grigorieva 's family lawyer , Alan Shifman , stepped aside and has been replaced by Los Angeles attorney Ronald Litz , her publicist confirmed . Gibson and Grigorieva are both scheduled to return to court on Monday .
NEW : TMZ declines to comment on documents ' source . TMZ published confidential court files in the Gibson child custody case . Gibson 's ex-girlfriend and her lawyer discussed the leaks with CNN 's Larry King . Oksana Grigorieva 's full interview will air on `` Larry King Live '' Wednesday night .