“We will make the request. Whether the Swedish authorities will hand him over, we don’t know,” Sinard Ajhanwong, head of Thai Interpol, told the Scandasia website.
The man is wanted in connection with the killing of a 43-year-old New Zealand man in a bar fight in holiday paradise Pattaya in August 2012.
The Swede was released on bail three days later after paying more that $20,000.
Unusually, his passport was returned in October after a Pattaya court granted permission for a two-week visit to Sweden. The man never returned.
Thai police have now opened an investigation into why the man was allowed to leave the country while under suspicion for murder, with investigators seek to assess whether any officials accepted bribes.
Murder is a capital offence in Thailand and this would render an extradition from Sweden extremely unlikely.
Sinard Ajhanwong explained that Thai police are aware that the extradition request may fail and therefore have an alternative plan to seek the man’s prosecution for murder in a Swedish court.