New Delhi, Aug 30 : The Enforcement Directorate (ED) has sent a notice to Janata Dal (United) MLC Radha Charan Seth and his son, Kanhaiyaa in connection with an alleged illegal sand mining case. The notice has been served under the Prevention of Money Laundering Act. They father-son duo has been asked to appear before the ED within 15 days. The notice was served by the Patna office of the ED. The JD(U) MLC reportedly owns Hotel Regal in Bihar's Arrah. According to sources, the ED recently conducted raids at more than 27 places in Bihar's Arrah and Patna; Jharkhand's Dhanbad and Hazaribagh; and in Kolkata, and froze as many as 60 bank accounts containing Rs six crore belonging to the JD(U) MLC. Apart from this, the ED also recovered cash around Rs 1.5 crore and property documents worth Rs 11 crore. The ED conducted raids at 22 places in February also. The ED's case is based on a police FIR. /IANS