A man and woman were arrested in Kanchanaburi after 10 kilogrammes of crystal methamphetamine were found in their vehicle.

The married couple’s 9-year-old daughter was a passenger in the car.

Police on Friday announced the arrest of Sombat Ouanseng, 50, and Chayaphan Srisuksai, 45, both natives of Songkhla province.

They were travelling in a sport-utility vehicle with Bangkok licence plates. 

Ms Chayaphan is an official at Wang Ka tambon administration organisation in Sangkhla Buri district of Kanchanaburi, according to police.

Evidence had pointed to Mr Sombat's alleged involvement in the drug trade, and his movements were being watched. 

When Mr Sombat left his house in Sangkhla Buri district on Thursday morning, police followed his car.  He was stopped at a checkpoint in Thong Pha Phum district around 11.30am.

Officers searched the vehicle and found 14 packages containing crystal meth, 10 kilogrammes in total, according to police.

Mr Sombat was taken back to his house in tambon Nong Lu of Sangkhla Buri district. A search found nothing illegal there. He was then taken to Thong Pha Phum police station.

Urine tests on Mr Sombat and his wife were negative for drug use. They were charged with collusion in possession of illicit drugs.

Ms Chayaphan denied all charges.

During questioning, Mr Sombat allegedly confessed to all charges, but said he acted alone and his wife was not involved.

He told police he had first taken his wife and daughter to see a doctor that day, and was on his way to Muang district with the drugs he was carrying.

He allegedly said it was his seventh delivery and that he’d been paid 30-40,000 baht for each.

The arresting team handed the couple over to Thong Pha Phum police for legal action. Investigations are continuing.