Lazar Kolev, defendant in Bulgaria's high-profile Belneyski murder case, is the perpetrator of the brutal killings, the key witness in the case, Vladimir Savov, declared from the stand Wednesday.

Sisters Rositsa (18) and Kristina (15) Belneyski went missing in January 2006, after leaving a disco bar in the town of Pazardzhik. The sisters were found dead at the beginning of February near the town of Peshtera.

Kolev and Savov shared the same cell at the National Investigation Services in Sofia.

According to Savov, in a bout of depression, Kolev confined in him he killed the girls during a drunken rage.

The investigator had placed a wiretap on the witness' collar, but the defendant had been warned by his lawyer he might be spied on, so Kolev used gestures and face mimics to make the confession. He whispered in Savov's year and turned on the radio to silence the words.

According to the witness, the older sister Rositsa could not bear the sexual violence and jumped from the car. The defense counsel, in the face of prominent attorney, Marin Markovski, established a discrepancy in the testimony, because during the interrogation before the trial Savov had not mentioned Rositsa being subject of violence.

Kolev told the magistrates, in Savov's presence, he never admitted to the latter knowing the sisters.

Savov, on his part, denied any pressure on the part of the prosecutor, or receiving any benefits for his testimony.

The other key witness, Kolev's uncle, Paun Lazarov, stated he had been pressured by the prosecutor; denied ever paying to provide an alibi for his nephew and declared Kolev did not kill the sisters.

Lazarov further explained he had given two DNA samples and was paying for Kolev's defense only because he wanted to help his sister, Kolev's mother.

The mother of one of the defendant's girlfriends contradicted her earlier, pre-trial admissions she had been given money by the uncle to say Kolev was at her house on the night of the murder.

She said Kolev was a "good boy," and she could not confirm her earlier statements about being paid to provide a cover-up and did not remember exactly when the defendant was at her house.

The girlfriend, Violeta Vitekova, who at the time of the murder had been only 12 and a school drop-out, told reporters Kolev had never been aggressive towards her and he could not been able to commit such cruel act. She denied getting pregnant by the defendant.

Vitekova's step-father also took the witness stand. He is currently serving jail time for DUI and has previous sentences for fraud. He confirmed the uncle had given him money to provide an alibi, but said he no longer remembered the exact night Kolev spent at the house.

The trail is ongoing.