Murder suspect, Krisana Suwanphithak, has recanted earlier testimony in which she admitted killing her teenage maid five years ago, and accused her tomboy friend instead.
Ms Krisana, 45, a former beauty pageant contestant, previously admitted all charges, including injuring the victim and causing death, according to police.
However, the suspect has now retracted her confession, blaming her close friend, identified only as Pratthana, as the real killer.
Insisting on her innocence, Ms Pratthana has told police she did not beat or assault Ms Krisana's maid, Jariya "Nong Nam" Srisak.
On the contrary, Ms Pratthana said she was also a victim of Ms Krisana, as she had been beaten by her, said a source.
Ms Pratthana, 32, had lived at Ms Krisana's house since she was 19, and worked as her personal assistant.
She claimed Ms Krisana used an aerosol can to beat her the same way she did Jariya, but luckily the injuries were not as severe, the source said.
The accusation Ms Pratthana made against Mr Krisana, fingering her as the real killer, matched testimony given by three other witnesses, the source added.
Ms Pratthana refused to talk to the media Tuesday, adding she was consulting others about her next steps. The initial findings from the case, prepared by investigators of the Crime Suppression Division, have been forwarded to CSD chief Maitri Chimchoet.
According to a police source, testimony from eight people and witnesses are contradictory and police are discussing how to deal with the problem. Ms Krisana is currently in CSD custody.
The suspect will face more charges, including premeditated murder and concealing a body, if investigators find more evidence, Central Investigation Bureau chief Thitiraj Nhongharnpitak said earlier.
Ms Krisana, who was described by her close associates as hot-tempered and violent, is the prime suspect in the murder, thought to have taken place in Phetchaburi in April in 2015. When she was arrested in Chachoengsao province on Sunday, she claimed three other people apart from herself were involved in the killing.
A body thought to belong to Jariya was discovered in Phetchaburi. Police suspect the victim was buried after the murder. Police are waiting for an autopsy report to confirm the body is that of Jariya, and tests on fingerprints found on the victim's clothes.