Two Akhil Bharatiya Vidyarthi Parishad leaders, including its state unit chief, were formally arrested on Thursday for murder of Prof H S Sabharwal in an attack during college elections in Ujjain, Madhya Pradesh, police said.

Madhya Pradesh ABVP President Shashiranjan Akela and Secretary Vimal Tomar, who were on Wednesday sent on judicial remand till September 7, were booked for Sabharwal's killing under Section 302 of Indian Penal Code, police said.

Akela and Tomar, who were shown by TV channels threatening another professor M L Nath after student union elections at Madhav College were cancelled following complaints of irregularities on August 26, were named in the case registered earlier against unknown persons, they said.

The FIR on death of Sabharwal was filed on a complaint of the college peon Komal Singh Sengar, police said.

Apart from the murder case, police had booked students for manhandling and throwing mud at Nath and arson and violence at the college. The ABVP leaders and Sanjeev Jain, a worker of Nationalist Congress Party's Disha Kisaan Sangathan, were among eight persons arrested for the attack on Nath. Five of them were earlier released on bail.

About 23 National Students Union of India workers were arrested for arson and violence at the college and sent on judicial remand till September 13.