Mexican authorities have charged three people over the disappearance of Perth brothers Jake and Callum Robinson and their American friend Jack Carter Rhoad.
It comes after four bodies were discovered in the Baja California area early on Saturday morning, Australian time.
The site is understood to be near where the brothers and their mate had been on a surfing trip before they were last seen on April 27.
“Three bodies were found south of the city of Ensenada, and they were recovered in co-ordination with other authorities during a specialised operation because they were found in a zone of difficult access,” the State Attorney-General’s Office said in a statement.
“This was done as part of the search for two Australians and one American reported missing.”
Two hours after releasing that statement, Mexican authorities revealed another body — believed to be “older remains” — had been found.
But Baja California Attorney-General Maria Elena Andrade Ramirez later confirmed it was not connected to the current case.
Heavily armed police guarded the grim scene as the recovery operation took place at Punta San José in the township of Santo Tomás.
It was reported the bodies were found in a well more than 15 metres deep, according to the San Diego Union-Tribune and Mexican publication Zeta.
Firefighters and personnel from the State Attorney-General’s Office (FGE) worked to carefully to remove the bodies.
The town is about a 90-minute drive from Ensenada, where the Robinson brothers and Mr Rhoad were last seen before they were meant to travel north to Rosarito.
Authorities believe the bodies are that of the three men, but are awaiting forensic testing results for confirmation. Two men and a woman have since been charged with the “forced disappearance of people” — a crime akin to kidnapping.
Ms Andrade Ramirez said evidence obtained by authorities so far suggested that the three men were killed in an attempted carjacking gone wrong.
“When they tried to get the vehicle, the victims opposed the robbery,” Ms Andrade Ramirez told 7NEWS.
“The robbers were armed with a firearm and then apparently shot the victims.”
The chief prosecutor said they believed the attempted robbery was not linked to organised crime, despite the presence of gangs in the area.
But, she said that would not stop authorities from bringing justice to the men and their devastated families.
The two men and woman in custody are expected to be charged with murder.
“This crime won’t be unpunished,” Ms Andrade Ramirez said.
“I believe that you noticed that we acted in a fast way to get the first results. The investigation is still open, but it could change as we get more information.”
The site where the bodies were discovered was near a popular remote surfing spot known as the “Lighthouse”. And it is in the same area where the missing men’s tents were found, where blood was reportedly found, and where the burnt-out Chevrolet Colorado ute they had been driving was found on Friday.
Ms Andrade Ramirez said evidence found along with the tourists’ abandoned tents was linked to the three people in custody.
Investigators are continuing to comb the isolated beach area, where the bodies were discovered, for any additional evidence.
The three men have been missing since Saturday, April 27, after they didn’t arrive at their accommodation in Rosarito.
Callum, 33, a talented lacrosse player, had been living in San Diego.
His brother Jake, 30, a doctor, had just travelled overseas to visit him for a surfing trip.
Their parents, Debra and Martin Robinson, have travelled to Mexico to be closer to the investigation.
In a statement on Friday, they spoke proudly of their highly successful sons, who were meant to be on “a trip of a lifetime” when communication from them abruptly stopped.
They talked of how the elder brother Callum had made the decision to “follow his dream” by moving to the US to play lacrosse — a sport he had since gone on to represent Australia in.
And how doctor Jake had left Australia just two weeks ago to join his brother, before he was due to take up a new role at University Hospital Geelong in Victoria. The pair had attended US music festival Coachella before they drove across the border to Mexico to surf for a few days.
The distraught parents also thanked well-wishers for their support and the various authorities involved with the investigation.
“We thank everyone, especially the police, DFAT, Australian embassy staff and other authorities, for continuing the search to find the answers we desperately seek,” they said.
The siblings’ disappearance triggered a multi-state response from Mexican authorities, the Australian and US embassies, Australian Federal Police and the Federal Bureau of Investigation.
Mrs Robinson put out a desperate plea for assistance on social media and Facebook travel pages in the hope that someone had seen her sons.
That post was soon dispersed worldwide as friends and family of the men shared or made their own posts about the disappearance.
Initial investigations led Mexican police to a 23-year-old woman who they tracked down after a mobile phone belonging to one of the missing tourists was pinged by a cell tower.
The woman had the mobile phone as well as illicit drugs on her, leading to her arrest and further questioning by authorities over the men.
“A working team (of investigators) was at the site where (those arrested) were last seen, where tents and other evidence was found that could be linked to these three people we have under investigation,” Ms Andrade Ramirez said.
“There is a lot of important information that we can’t make public.”
Although drug cartels are active in the area, she said, “all lines of investigation are open at this time” and that investigators “cannot rule anything out”.
Officials from the Department of Foreign Affairs and Trade confirmed on Saturday they were providing ongoing assistance to the Robinson family, who live in the Perth northern suburb of Sorrento.
The department also confirmed the Australian Embassy in Mexico City was continuing to work closely with the Australian Federal Police and local authorities on the matter.
“The Department of Foreign Affairs and Trade recognises this is a very distressing time for the family and is in regular contact with them to provide support,” a spokesperson said.
“Owing to our privacy obligations we are unable to provide further comment.”
The department recently reviewed and updated its travel advice for Mexico.