Sister Amala was found dead by other nuns at the Carmel Convent in Pala near Kottayam.
Kerala Police on Sunday claimed that the man who was arrested by Uttarakhand Police from Haridwar has been identified as the accused in the murder of an elderly Catholic nun in the state and displays all signs of a "psychopathic killer."
A team of police officials from Kerala brought the accused, Satheesh Babu, on Sunday to the state after securing his custody through transit warrant from the Uttarakhand police on September 25.
After questioning him at the Police Club in Kottayam, ADGP K Padmakumar claimed, "The scientific probe by our investigation team has found that it was Satheesh Babu who murdered the 69-year-old sister, Amala, at her Lisieux Carmel Convent at Pala (in Kottayam) on September 17."
All circumstantial evidence, including fingerprint analysis and his telephonic conversation, prove his role in the nun's killing, the ADGP claimed.
Noting that five such cases of targeting nuns at various convents in and around Pala have been reported since November last year, Mr Padmakumar said, adding that the nuns who came under attack were aged over 60 and all of them suffered wounds on the back of their heads.
"It gave an indication that it was a single person behind all these assaults. In one case, two mobile phones were stolen. Truly speaking, all these were done by a person, who enjoyed a kind of sheer pleasure from doing it, displaying signs of a psychopathic killer," he said.
He said police will seek his custody for a detailed investigation after producing him in court.
Satheesh Babu, a native of Kasargod, was arrested last week from a guesthouse of a Kerala Ashram at Haridwar after Kerala police gave a specific input about his presence there.
Kerala police, who had put mobile phones of Satheesh's relatives and friends under surveillance, came to know from a message received by his elder brother from Haridwar that the murder accused was camping at the guest house of the Ashram.
The information about the crime was immediately passed on to Uttarakhand police and he was arrested, police said.
Police, which conducted the probe with the help of its cyber cell, had said Satheesh Babu was a serial offender targeting convents.
Sister Amala was found dead in a pool of blood in her convent room. A deep injury with a sharp-edged weapon on her back and minor wounds were found on her forehead, police had said.