The Central Bureau of Investigation (CBI) Monday summoned Trinamool general secretary and former railway minister Mukul Roy for questioning in connection with the multi-crore rupee Saradha scam.Confirming that he has been called for questioning, Roy - presently in Delhi - said he will appear before the CBI once he returns to Kolkata."Question doesn't arise about any summons but I have been informed by the CBI. I am here (Delhi) for a day or two, and once I go back to Kolkata, definitely I will meet the CBI people," Roy told reporters in Delhi."I have never done any illegal or immoral activities. They have called me but I am here. Once I return to Kolkata, I will meet them," added Roy.