Vikram Kothari. Pic/Twitter-@ANI

The CBI today arrested Rotomac owner Vikram Kothari and his son Rahul, both directors in the company, for alleged default on loan repayments to the tune of Rs 3,695 crore, officials said. Kothari, who was called at the agency headquarters here for questioning, and Rahul were not cooperating in the investigation that led to their arrest, they said.