A British retiree was arrested over a knife fight with his Thai wife.

The expat allegedly swung a 15cm-long blade at Thai woman Chanyapak Thanakulwittaya, 27, during a row at a condominium in Pattaya, Thailand, in the early hours of January 30.

Police and medics who arrived at the scene said they found Chanyapak lying on the floor as she bled from a large cut on her hand.

She told police through tears that she had tried to snatch the knife from the British man, but was slashed when he waved the weapon to shake her off.

She said: 'We were fighting over the knife, but I was smaller and weaker than him. I was injured when he sliced at me while I was trying to grab it.'

Chanyapak was given first aid and rushed to a hospital.

Meanwhile, cops have detained the retiree for questioning at the police station. His identity was not released by authorities.

Police Lieutenant Sarawut Phutthaphonphiban said: 'This is a personal issue between the foreigner and his wife. Nobody else is involved.'

Former fishing village Pattaya became popular with American troops on 'rest and relaxation' breaks in the 1960s when the U.S. military had bases in Thailand. In the ensuing years, the coastal resort spawned into a semi-barbarous sex-tourism hellscape.

Embarrassed officials have made progress in gentrifying the region with family tourism projects but a ravenous nightlife industry and corrupt police have hampered their efforts, with undesirables from all nations still attracted to the seedy city.