A security guard at late Tamil Nadu Chief Minister J Jayalalithaa's Kodanad tea estate in Nilgiris district was murdered and another injured in an attack by unidentified persons, said police on Monday.

According to police, a group of unidentified persons fatally attacked security guard Om Bahadur while injuring Krishna Bahadur who also tried to stop them in the incident which occurred on Sunday night.

According to the police, the investigation is on.

Jayalalithaa had used the tea estate as her holiday retreat.