Lima, Peru (CNN) -- Joran van der Sloot was "tricked" into confessing to the murder of a Peruvian student, Stephany Flores Ramirez, he says in a Dutch newspaper article published Monday.
Peruvian police told him that if he signed the papers they gave him, he would be transferred to the Netherlands, he told De Telegraaf in a jail interview.
"In my blind panic I signed everything, but never knew what was written on them," he said.
He is scheduled to appear in a Peruvian court Monday for a hearing into the death of Flores, 21.
Van der Sloot was twice arrested over the disappearance of Alabama teen Natalee Holloway in Aruba in 2005, but never charged.
His mother said Saturday he was mentally unwell, De Telegraaf reported in what it called an exclusive interview with her.
Van der Sloot went to Peru to escape having to enter the high security section of a psychiatric hospital, Anita van der Sloot said.
She said he suffered severe psychological distress at the early death of his father, for which he blamed himself, she said, without giving further details.
She did not deny that he killed Flores.
Attorney Maximo Altez said van der Sloot's statement in court Monday will focus on how his rights were violated during the investigation.
Altez has maintained that the judge in the case should strike down van der Sloot's confession because he was not properly represented when he was interrogated.
But Peruvian police have defended the interrogation and said van der Sloot's confession was acquired legally.
According to transcripts of his confession, van der Sloot said he elbowed Flores in the face before strangling her and then suffocating her with his shirt.
The transcripts -- provided to CNN by a police source -- provide shocking details and give the public its first glimpse of why van der Sloot says the alleged murder took place. The source has not been named because he was not authorized to pass along the material.
"There was blood everywhere," van der Sloot said in the transcripts. "What am I going to do now. I had blood on my shirt. There was also blood on the bed, so, I took my shirt and put it on her face, pressing hard, until I killed Stephany."
Peruvian authorities have charged van der Sloot with murder.
Van der Sloot told authorities he attacked Flores on May 30 after she read an e-mail on his computer connected with the Holloway case.
In the transcript, van der Sloot said that after Flores read the e-mail, she punched him in the face.
"At that moment impulsively, with my right elbow I hit her in the face exactly on top of the nose," van der Sloot said. "I think she started to faint. It affected me so that I grabbed her from the neck and strangled her for a minute."
Van der Sloot said he had a quick thought to try and hide the body but instead fled.
He was arrested in Chile on June 3 and was returned the next day to Peru. Along with killing Flores, who had a broken neck, he took money and bank cards from her wallet, police said.
Van der Sloot told police in Chile a different story of how Flores died when he was arrested there, according to transcripts. He blamed the death on robbers who had waited for him at his hotel in Peru.
"There was a man coming from the access door with a knife in his hand," van der Sloot said. "The man with the knife hit her in the face, making her bleed through the nose."
But Peru authorities said they had overwhelming evidence pointing to van der Sloot, and when he was transferred to Peru, van der Sloot confessed to the crime, police said.
Van der Sloot said he was in Peru for a poker tournament and had met Flores while he was gambling.
Police have said they think van der Sloot killed Flores to steal money she won from gambling.
Van der Sloot offered a different motive.
"After I responded with hitting her, I feared that she would go to the police and they would detain me for what was an impulsive act," van der Sloot said. "I think I wanted to kill her because I wasn't thinking."
Van der Sloot is being held in a high-security area of the Miguel Castro Castro prison where only two of 10 cells are occupied, and he has no contact with inmates in the general prison population.
He is under guard 24 hours a day, authorities have said.
The only other inmate in the area is alleged Colombian hit man Hugo Trujillo Ospina. The two have spent some time together in a common area where there is a television set and weights made of broomsticks and soda bottles, authorities said.
There is the possibility that van der Sloot will be integrated with other segments of the prison population.