A DMK functionary, whose house was raided by Income Tax sleuths on Friday, complained of chest pain and was hospitalised, police said.
Krishnan, the party's Coimbatore Urban West district in charge, was admitted to a private hospital, where he was advised to take rest for a day.
Sources said the raid was part of an exercise by the department at various locations in Tamil Nadu since October 28.
Krishnan, his wife and some relatives were questioned, party sources said.
Doctors at the hospital where he was admitted said the chest pain could be due to a possible increase in blood pressure and advised him a day's rest, they said.
CPI(M) MP P R Natarajan visited the hospital and enquired about his health condition.
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