The victim identified as Akhil, was brutally assaulted with sticks and bricks allegedly by a group of men near Karamana.
The murder took place on Saturday afternoon when the victim, who worked as a mid-day meal helper at a government school, was returning home from her workplace.
The prime accused in the murder of a 26-year-old man in Thiruvananthapuram in Kerala a day ago was nabbed, police said on Sunday, 12 May. The accused was picked up from a hideout in neighbouring Tamil Nadu. He was taken into custody and is being interrogated, they said without divulging further details.