Kochi: Kerala Police has "the suspect" in the murder of law student Jisha in its custody, Chief Minister Pinarayi Vijayan said here on Thursday, suggesting a major breakthrough. "This is certainly going to be a feather in the cap of the police probe team," Vijayan told reporters about the investigation into what appeared to be a case of rape and brutal murder of the 27-year-old Dalit woman. While police is tight-lipped about the investigation, sources in the know said an Assamese youth and four of his friends have been arrested for the crime. Police has sent the DNA samples of the key suspect for verification to see if they match with the saliva and blood samples found on Jisha's body, said the sources. The forensic report may come as soon as later on Thursday. Jisha was found dead on April 28 at her home in Perumbavoor in Ernakulam district by her mother Rajeshwari who works as a casual labourer. Her body bore injuries in a way that gave rise to suspicions that she was raped before being killed. The case was reminiscent of Jyoti Singh 'Nirbhaya' who was gang-raped and brutalised on December 16, 2012, in a moving bus in New Delhi. The murder attracted national headlines and became a cause célèbre in Kerala's election season. The Left Democratic Front (LDF) said it reflected the slide in law and order that the ruling Congress-led United Democratic Front (UDF) had allowed. The opposition also promised to book the culprits within hours if elected to power. The newly elected LDF government, which assumed office on May 25, changed the entire team probing the case and replaced Director General of Police (DGP) T.P. Senkumar with Loknath Behra.