A Dutch man who confessed to stabbing to death a young British woman holidaying in Indian Kashmir says the "the devil" took over his body.
Richard De Wit, 43, told police he had murdered Sarah Groves, who had been staying on the New Beauty houseboat at Dal Lake in Srinagar for two months with her boyfriend.
He has yet to be charged.
"He has confessed that he committed the murder under the influence of some drug. We have sent his blood sample for testing to ascertain the facts," deputy inspector general of police Afadul Mujtaba said.
Mr De Wit was arrested on Saturday as he tried to flee in a taxi near Qazigund, 75km south of Srinagar, soon after the 24-year-old was found dead in a pool of blood in her houseboat cabin.
Ms Groves' boyfriend Saeed Shoda, 25, has told the Daily Mail in London that he confronted Mr De Wit in his holding cell.
Mr Shoda, who "fell in love" with Ms Groves in Goa in January, said he begged the accused for answers.
"I don't understand why he killed her. He had no reason to kill," he told the Daily Mail. "I saw him at the police station and I asked him why. I begged why, why did you kill her? He brazenly replied: "I killed her; that's it. The devil took over my body". He isn't normal."
Mr Saeed is now traumatised and "cannot think of a future without Sarah".
"We'd only known one another for three months so it was too early to talk about marriage and children, and I have no idea if we would've got married, but she was a perfect girl," he said.
Ms Groves, who is from Guernsey, was due to fly home to the UK next week.
"I can't explain what I loved about her but she was different from others. I've been in the tourism industry since my childhood and I've met hundreds of foreigners but she was just so charming," Mr Saeed said. "I liked the way she thought about life. She was full of energy and wanted everyone to be positive."
"I am so traumatised about her death. I can't think about the future without her now. I just want justice for her and answers."
Mr Saeed told the Daily Mail he had spoken to Ms Groves' family.
"The family are devastated but will still come to Kashmir. I don't know how to face them because they had trusted me. It's an awful situation, just so sad," he said.
Police, who have yet to establish a motive for the crime, said they had spoken to Mr De Wit's wife in Holland who told them that her husband has had a history of psychiatric problems.
Mr De Wit, who had been staying in an adjacent room in the same houseboat as the victim after arriving on Thursday, broke the latch on her cabin door and tried to escape in a small boat after killing her, police said.
Mujtaba said a sexual motive for the crime had not been established.
Ms Groves was due to fly back to the UK next week.
The gruesome incident comes after a 39-year-old Swiss cyclist was allegedly gang-raped and robbed by six men in the central Indian state of Madhya Pradesh last month.
Also last month, a British woman dental hygienist suffered leg injuries when she jumped from a hotel balcony in the northern tourist city of Agra, fearing a sexual assault by hotel employees.
The safety of women in India has been in the spotlight since the fatal gang-rape in December of a 23-year-old physiotherapy student on a bus in New Delhi, which sparked nationwide outrage.