"Kanhaiya is in a bad situation. He is in a semi-conscious state. There is a possibility of internal damage to (his) organs," Umar Khalid, his friend in the Jawaharlal Nehru University (JNU), told IANS.
Khalid said Kanhaiya Kumar started vomitting on Thursday morning after which he was "rushed to a hospital".
Kanhaiya Kumar, the JNU Students Union (JNUSU) president, and 19 other students are on an indefinite hunger strike since April 28 to protest against the punishment handed out to them by a high-level committee that probed the controversial February 9 Kashmir event on the campus.
"The health of the rest of the students is also deteriorating fast. All students have lost around 4-6 kg of weight," Khalid said.
"It has been the 8th day of the indefinite hunger strike... Still the JNU administration remains unmoved," said Khalid, who has been rusticated from the university for one semester.