The Central Bureau of Investigation on Monday grilled former Rajasthan minister Mahipal Maderna's wife Leela and two sons of Member of Legislative Assembly Malkhan Singh in connection with the Bhanwari Devi abduction case.
They are all being quizzed at the circuit house in Jaipur, CBI sources said.
Osian MLA Maderna is under judicial custody, while Luni MLA Singh has skipped questioning for the past several days despite repeated summons.
The probe agency may seek his arrest warrant today.
The agency has questioned Singh's sons a few times to know the whereabouts of their father, who had sought exemption from questioning on heath grounds till last Friday by moving an application in the court.
Bhanwari, 36, posted as an auxiliary nurse at a sub-centre in Jaliwada village, has been missing since September 1.
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