The wife of Phetchaburi multiple murder suspect Supat Laohawattana has been denied bail.

SHOW ME THE WAY: Phetchaburi’s Tha Mai Ruak police chief Pol Col Pichai Pokpong seeks divine intervention to help find more people believed buried in a pineapple orchard.

Wilasa Janbanchorn was arrested on Friday at a friend's home in Bangkok on charges of theft, possession of stolen items and illegally restraining people against their will.

These are the same charges facing Pol Col Supat, who may also be charged with murder based on the pending results of forensic tests on three skeletons dug up in his pineapple orchard.

The Phetchaburi Court judge Saturday reasoned that Mrs Wilasa poses a flight risk and may interfere with witnesses and evidence.

Pol Col Supat, a former doctor at the Police General Hospital, is suspected of killing up to four people _ married couple Samart Noomjui and Orasa Kerdsap, who have been missing since 2009, and two Myanmar nationals who worked at his orchard.

Investigators yesterday questioned Mrs Wilasa for more than eight hours, following her confession that she had witnessed her husband talking with the couple and later heard gunshots.

She said she did not know if Pol Col Supat killed the couple as she had only heard the shots, but did not see anything.

Mr Samart's father, Sawang Noomjui, talked with Ms Wilasa for about two minutes inside a cell at Tha Mai Ruak Police Station in Tha Yang district of Phetchaburi.

Mr Sawang said after emerging from the conversation that Ms Wilasa admitted she had seen her husband with the couple but she had no idea where he had taken them to.

"I refuse to believe she doesn't know [what happened to them]," Mr Sawang said.

Mrs Wilasa was later taken to Phetchaburi prison.

Meanwhile, police have continued digging up land in Pol Col Supat's orchard in the hope of finding either additional bones or more clues about the murders after the three skeletons were uncovered there two weeks ago.

About 30 locals joined in the digging yesterday.

A 5,000 baht reward will be given to anyone who can find more bodies buried underground there, said Pol Col Pichai Pokpong, chief of Tha Mai Ruak Police Station, which is handling the case.