Warning, you may find the images disturbing.

Blurring and subtitles by FRANCE 24.

The footage was filmed on October 13 and posted online on October 20. How the footage found itself on YouTube and Facebook is still a mystery. The only explanation is that it was posted online by one of the aggressors.

The youths and the police agree that they were arrested by officers - but the police deny having any involvement in the abuse which followed, pointing out that they use different rifles and not the AK-47 seen in the video (at 00:31 seconds we see what looks like the shadow of a rifle).

Nayarit governor Ney González said on October 25 that "Justice cannot be carried out at home" and that "They're as bad as each other". He gave the district attorney and the head of police a 12-hour time limit to produce substantial findings on the case.

On Monday morning, the district attorney announced that four suspects had been arrested. Apparently they had been boasting about the incident in a local bar, and somebody phoned the police. An AK-47 was indeed found in their possession - albeit a toy one.

Antonio Tello is a radio journalist in Tepic. He was the first person to draw attention to the footage, which he published on his blog Nayarit online Friday 23 October, two days after being made aware of it.

Someone who knew the teenagers sent me a tip on Facebook. The videos were entitled ‘Ratitas de Tepic' [scoundrels of Tepic], and captioned ‘Look at what happened to them for thieving from my house'. The original clips were gone by then, but someone had been able to download and repost them beforehand.

Several days after posting the videos I received an anonymous email, leading me to one of the boys. I was then able to speak to the family of another of the teenagers. What I was able to gather from the two accounts, is that they were kicked and slapped by a group of around eight men and two women. They were repeatedly told by their captors that their hands would be chopped off and they would die and be buried beneath the courtyard. Their heads were shaved with a razor. One of them told me that they were whipped with a tree branch and given electric shocks using some sort of prod. I saw the marks on his body. None of them said anything about being raped however.

They were then abandoned in one of Tepic's main avenues, beaten and half naked. Several neighbours called the police, who arrived and questioned them. The boys said only that they had been assaulted. Incredibly, the police left them there and the teenagers took taxis home. The police report confirms this and details that the boys did not want to file a complaint.

Everyone in Nayarit is talking about the videos. A lot has been said about the involvement of police and drug traffickers in this affair, either separately or jointly. Nayarit used to be one of the safest states in Mexico, but recently it has been plagued by urban delinquency and organized crime, mostly linked to drug trafficking. Some say that the house the teenagers broke in to belonged to a prominent drug kingpin. And police brutality isn't unheard of in this state. However, there is no actual evidence of either traffickers or officers playing a role in this case.

According to the teenagers, it was the police who caught them burgling the house. They say that they were briefly taken to the attorney general's office, and then handed over to the men, instead of being charged. Normally the police would open a file, question them and then transfer them to an association for underage offenders.

I visited two of the teenagers' homes and contrary to what most people might think, their situation is not one of extreme poverty. These boys come from middle class families and go to private schools. As they said themselves, they have a [drug] addiction problem and have stolen in the past in order to sustain it."