State home minister Ramesh Chennithala asked the Kochi range inspector general to constitute a special investigation team to probe the case.
The incident might become a factor in the assembly polls on May 16 where the ruling United Democratic Front is locked in a tough battle with the Left Democratic Front.
The crime also comes amid a nationwide debate on caste atrocities following the suicide of Dalit PhD student Rohith Vemula and the alleged honour killings of inter-caste couples in neighbouring Tamil Nadu.
The woman was alone at her home on Thursday night when the incident took place and was found by her mother, sources said. She is survived by a married sister and father who were living separately.
Police have been unable to arrest any suspects, sparking anger among local residents, who have mounted a social media campaign to ensure justice for the victim.
Many who joined the campaign blamed the authorities for neglecting the case due to assembly poll rush. “We have formed a SIT and investigation is on. Since the area is heavily populated by inter-state workers the probe team is exploring all possibilities,” said the home minister.
The brutal gang rape of a young medical student in south Delhi four years ago by a group of men had sparked widespread outrage. Thousands of people protested on the roads, forcing the government to bring in a more stringent law to deal with rising crimes against women.