Speaking to reporters on Tuesday, Jan 12, police officials said, "A gang killed Vetrivel by mistake as the intended target was another police named D Sivasubramanian."
Vetrivel was in the Alwarkurichi police station in Tirunelveli district of southern Tamil Nadu.
Police arrested D Sivasubramanian's wife S Sivakami and Ayyappan, a friend of Sivakami's brother on Monday, Jan 11.
Meanwhile, A Subramanian of Tuticorin district surrendered in a Madurai court in connection with Vetrivel's murder.
With this the number of people in police custody in connection with Vetrivel's murder has gone up to six.
Vetrivel was attacked on a main road in Tirunelveli Jan 7 and bled to death in front of ministers and officials.