1996–2001 Tamil Nadu Legislative Assembly by-elections
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8 vacant seats in the Legislature of Tamil Nadu  | ||||||||||||||||
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By-elections to Natham and Thiruvattar constituencies were held in Tamil Nadu, India, on 5 and 11 September 1999 respectively. Elections for three state assembly constituencies, Nellikuppam, Tiruchirappalli - II and Arantangi were held on 17 February 2000.
In the first phase, TMC lost a seat to AIADMK and Dravida Munnetra Kazhagam (DMK) lost a seat to Communist Party of India (Marxist) (CPI (M)). In the second phase, AIADMK splinter party MADMK, was able to pick up a seat from AIADMK and DMK was able to hold on to its seats.