MDMK founder Vaiko and four other newly-elected Rajya Sabha MPs on Thursday took oath as members of the Upper House. Vaiko, PMK leader Anbumani Ramadoss and two candidates each from the AIADMK and the DMK were elected unopposed as Rajya Sabha members from Tamil Nadu earlier this month. When the House met for the day, Chairman M. Venkaiah Naidu called for oath or affirmation of the new members. All five members —new AIADMK Rajya Sabha members A. Muhammathjohn and N. Chandrasekaran, and DMK members N. Shanmugam and P. Wilson — took oath in Tamil. After taking oath, the new members were warmly greeted by Naidu and other members in the House by thumping of desks.