New Delhi, June 20 : The CBI on Tuesday was questioning Sam D'Souza, a private individual involved in the alleged extortion demand of Rs 25 crore in the Aryan Khan drug case, in which former Mumbai zone NCB Director Sameer Wankhede is an accused. D'Souza was summoned by the federal probe agency to join the investigation. On Tuesday, he arrived at the CBI headquarters here with his lawyers. "Sam D'Souza arrived with his lawyers. The CBI had issued a notice today at 10:30 a.m. summoning him for questioning at the CBI headquarters in Delhi," said a source. Previously, Wankhede was interrogated by the CBI in Mumbai. The accessed FIR makes shocking revelations. "Sameer Wankhede is accused of engaging in the buying and selling of expensive watches without disclosing this information. He also allegedly concealed details of his expenses during his foreign trips," stated the CBI source, quoting the FIR. The CBI has mentioned that while some individuals caught on the cruise were released, Aryan Khan was arrested. It also mentioned that K.P. Goswami, who appeared as an NCB official, was responsible for Aryan Khan's arrest. He was presented in such a way that he seemed like an officer of the NCB. Later, a demand of Rs 25 crore was made for a settlement, which was eventually negotiated down to Rs 8 crore. Initially, Rs 50 lakh was taken, but later some of the money was returned due to the case getting stuck. /IANS