The CBI on Thursday arrested Rotomac pen company owner Vikram Kothari and his son Rahul on charges of cheating a consortium of banks of Rs 3,695 crore (including interest) by siphoning off loans sanctioned to his company for procurement of wheat and other goods for export.The agency arrested them after daylong questioning at the Central Bureau of Investigation (CBI) headquarters in south Delhi's Lodi Road areaIt was the Kotharis' questioning for the fourth consecutive day since the CBI filed the case against him and his family, and raided their residential and office premises in Kanpur in Uttar Pradesh.The agency filed the FIR on Sunday night after getting a complaint against Kothari, his wife Sadhana and son Rahul, from the Bank of Baroda. Kothari is the Chairman and Managing Director of Rotomac while his wife and son are Directors.Kothari had obtained Rs 2,919 crore from Bank of India (Rs 754.77 crore), Bank of Baroda (Rs 456.63 crore), Indian Overseas Bank (Rs 771.07 crore), Union Bank of India (Rs 458.95 crore), Allahabad Bank (Rs 330.68 crore), Bank of Maharashtra (Rs 49.82 crore) and Oriental Bank of Commerce (Rs 97.47 crore), the FIR said.Kothari, his wife, son, firm Rotomac, some unidentified bank officials and private persons were booked on charges of criminal conspiracy, cheating and forgery under the Indian Penal Code and Prevention of Corruption Act. The Bank of Baroda complaint said that the banks had extended credit to the Kanpur-based firm and its related companies from 2008 onwards. The CBI had earlier confiscated several belongings of Kothari and his family, including laptops and mobile phones.