CHENNAI: T Pradeep (28), the accused who was arrested on Friday in connection with the murder of Tamil Nadu BSP President, K Armstrong had served as a Home Guard volunteer with the City police.
He was removed from service due to disciplinary issues, police sources said.
Pradeep's father is a serving sub inspector with the City Police's Armed Reserve.
Pradeep was hired by the main accused to do a recce and update them about Armstrong's movements.
He is also a relative of slain rowdy, Arcot Suresh who was murdered last year.
Pradeep's arrest increased the number of persons arrested in the murder to 18 thus far.
On Thursday, Police had arrested B Siva (35) of Mathur, an advocate, said to be a close associate of a notorious history-sheeter, who is under police scanner.
Eight persons including the brother of Arcot V Suresh were arrested within three hours of the murder of BSP leader Armstrong in Perambur on July 5.
Police had initially claimed that Armstrong was murdered in retaliation for Arcot Suresh's murder last year.
Meanwhile, In an early morning "encounter" on July 14 near Madhavaram, City police shot dead K Thiruvengadam (33), one of the suspects, when he allegedly opened fire at the police team which rounded him up after he fled while being taken to secure weapons used in the murder of Armstrong's murder.