Image copyright Facebook: Gili Trawangan, Meno, Air Image caption It is not clear whether those paraded admitted any guilt

Last week photos surfaced of two unidentified Western tourists being paraded around an Indonesian island in a "walk of shame" for alleged theft.

The images show a foreign man and woman walking alongside uniformed officers on the island of Gili Trawangan, with cardboard signs around their necks.

The signs read: "I am thieve [sic]. Don't do what I did...!!!"

The practice of parading those deemed to have committed crimes on the Gili Islands has gone on for many years although its exact origins are unclear.

After pictures of the incident appeared on social media, including an official Facebook page for the tiny islands, a number of questions have been asked about this unusual ritual.

What is the 'walk of shame'?

The head of West Nusa Tenggara province tourism office, Lalu Muhamad Fauzal, told the BBC that the practice of parading those considered to have committed crimes on the islands came out of an agreement between locals and police on the mainland.

Most such walks happen on Gili Trawangan, the largest and most developed of the three Gili Islands, off the coast of Lombok, about 40km (25 miles) east of Bali.

Image copyright AFP Image caption The idyllic islands are said to have low crime rates

Unlike Bali which attracts many tourists from around the world, the Gili Islands are much smaller and considered largely safe and peaceful. One circuit of the Trawangan is only about 7km (4.3 miles).

Why is it done?

The police do not have a permanent presence on the tiny islands of Gili Trawangan, Gili Meno or Gili Air. Instead, private security officers guard the islands, with support from mainland police when necessary. Most of the guards in the latest parade appear to be private, although at least one appears to be wearing a police uniform.

"Since there is no police enforcement on our little tropical paradise island, we have our own rules for thieves. If someone gets caught stealing, he or she has to parade around the island," Karina, from the island's Facebook page, told the BBC. "Later on the person will get banned from the island and is not allowed to return for a few years."

"It is to make people aware that they cannot visit a foreign country and take what they want without consequences," she added, echoing a widespread sentiment on the islands that the practice is both fair and effective.

"I never heard that someone was accused wrongly for a walk of shame".

Image copyright Oji Nuria Manggala Image caption Reports say the pair are Australian

Mr Fauzal agreed the parades could take credit for the island's low crime rate and their reputation for being far more peaceful than nearby Bali.

He added that most of those paraded are locals, although some are foreign tourists who were drunk or "forced to steal purses" as they had run out of money.

Is it legal?

It is not clear whether there is any formal legal basis for the parades, but as the accused generally avoid more serious sanction, some observers have suggested that embarrassment and a ban from the islands is preferable to a court battle and the possibility of a fine or worse.

Oji Nuria Manggala, who witnessed the parade, told the BBC that the guards accompanying the foreigners said the pair had been caught on security camera stealing a bike, and could not deny it.

However, it has not been possible to identify the pair to confirm the allegations or whether they had any opportunity to mount a defence.

And their rights?

The island's seemingly unsophisticated form of justice has surprised some with its deliberate lack of concern for the privacy of the accused, and clear legal process.

While locals the BBC spoke to did not share any doubts about the parade, others have suggested that even the innocent might be tempted to opt for public humiliation rather than face formal charges under the Indonesian justice system, which is sometimes criticised for corruption and a lack of transparency.

Reporting by BBC Indonesian's Endang Nurdin and the BBC's Simeon Paterson.