Media reports say around 40 students of Dr. Ambedkar Law University and Dr. Ambedkar Government Law College in Chennai, continued with their fast on Wednesday.
Students are demanding an independent probe against Colombo for alleged war crimes. Moreover, they are also asking for a separate Eelam (homeland for Tamils).
Earlier, police arrested eight Loyola College students on fast and they were taken to Royapettah hospital for treatment.
Police action sparked protests by students of nearly nine colleges in Chennai who condemned the arrest of the students who were protesting peacefully.
"We were told that our children have no health problems but we can meet them only after 2 p.m. My son has not eaten anything for the past three days but since he was doing good for our people, I did not stop him," said Kalaiselvi, a mother of a protester on hunger strike.
The protesting students have received support from leaders such as MDMK chief Vaiko and CPI national secretary D. Raja. DMK chief M. Karunanidhi had urged the students to withdraw the fast and resort to democratic forms of protest.
The emotive Sri Lankan Tamils issue has gained momentum in Tamil Nadu following pictures relating to the alleged cold-blooded killing of slain LTTE chief V. Prabakaran's 12 year-old son Balachandran surfaced in the media recently.