In fresh trouble for controversial self-styled godman Asaram Bapu, an FIR has been registered by two sisters from Surat against the spiritual guru and his son Narayan Sai. According to the FIR, Asaram raped the elder sister at Ahmadabad Ashram and his son raped the younger one in Surat between 2002 and 2004. Surat police commissioner Rakesh Asthana has said that there is a possibility of Narayan Sai's arrest. Asaram, 75, was arrested in August on charges of sexually assaulting a schoolgirl and has been in prison in Jodhpur in Rajasthan since then. Shilpi, one of his key aides and the warden of Asaram's 'ashram' in Chhindwara district of Madhya Pradesh where the alleged sexual assault took place, too has been arrested and sent to judicial custody.