Shares of dairy foods giant Juhayna plunged as much as 17% in trading yesterday before regaining some ground to close the day down 10.6% on news of CEO Seif Thabet’s arreston Saturday as part of what Reuters says is an investigation into the alleged financing of terror groups. Seif’s father Safwan Thabet was arrested late last year as part of a probe into what security officials described as “financial irregularities.” The company confirmed Seif’s detention in an EGX disclosure (pdf) Sunday, saying it had no further information to disclose.