SAO PAULO, Sept 5 (Reuters) - Shares of JBS SA slumped the most in 14 weeks on Tuesday on concerns that a plea bargain deal between the meatpacker's controlling shareholders and Brazilian prosecutors may be partially revoked for allegedly hiding criminal evidence.
Late on Monday, Prosecutor-General Rodrigo Janot said Joesley Batista, who controls JBS with his older brother Wesley, and a fellow witness seemed to have inadvertently recorded a four-hour conversation discussing crimes not covered in their plea bargain.
Janot, who leaves office later this month, said Joesley Batista and the other witness could lose benefits from the deal, which include immunity from prosecution.
In a statement on Monday, J&F Investimentos SA, an investment holding firm through which the Batistas controls JBS, said Janot had hastily interpreted the recording, which contained "considerations of hypotheses" and did not compromise the good faith of the witnesses.
The Batistas confessed in May to bribing 1,893 politicians and handed over evidence to prosecutors that linked President Michel Temer to endorsing hush payments to a possible witness in a graft probe.
The stock fell as much as 11 percent at open, but pared losses by mid-morning trading. Shares were down 5.1 percent to 8.14 reais at 11:36 a.m. local time (1436 GMT), extending losses this year to 28 percent.
(Reporting by Guillermo Parra-Bernal and Bruno Federowski; Editing by Meredith Mazzilli)