A dream trip for three surfers on the Baja California coast in Mexico suddenly turned deadly.

Australian brothers Jake and Callum Robinson and American Jack Carter Rhoad appeared to have stopped to surf between Punta San José and La Bocano when they were attacked on either April 28 or 29. All three were found dead with gunshot wounds to the head, their bodies had been dumped in a well around four miles away in a site that is “extremely hard to get to.”

A fourth body that had been there for much longer was found under the remains of the three men. The trio had planned to take a popular route for what was supposed to be the surfing trip of a lifetime, starting from Ensenada and camping along the Pacific coast as they made their way to Rosarito further north.

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Callum Robinson, 33, his brother Jake, 30, and their American friend Jack Carter Rhoad, 30, from San Diego, disappeared without a trace (
Image:
AFP via Getty Images)

But they never made it to their final destination. Police quickly realized something had gone wrong when they arrived at the trio’s last known campsite.

Authorities found bloodstains and became suspicious of an attack because of marks “as if heavy objects had been dragged.” Chief state prosecutor María Elena said there was “no way to ask for help when the attackers showed up.”

Andrade Ramírez theorized the killers drove by and saw the foreigners’ pickup truck and tents and wanted to steal the truck's tires and other parts. But “when (the foreigners) came up and caught them, surely, they resisted.”

Callum Robinson, left, and his brother Jake (
Image:
Callum Robinson/Instagram)
Jack Carter Rhoad, 30 (
Image:
callum10robinson/Instagram)

Andrade Ramírez added: "The evidence suggests they (the killers) did not know where they were from.” The group’s tents were burned in an attempt to destroy evidence.

Later a gun was found in what is believed to be the assailants’ truck. Of the well, Andrade Ramírez said the assailants must have had “previous knowledge of it” and added that “It was literally almost impossible to find it.”

Prosecutors have said they were questioning three people in the killings. Two were caught with methamphetamines. One of them, a woman, had one of the victims' cellphones when she was caught. Prosecutors said the two were being held pending drug charges but continue to be suspects in the killings.

A post from Callum Robinson's Instagram (
Image:
Instagram/callum10robinson)

A third man was arrested on charges of a crime equivalent to kidnapping, but that was before the bodies were found. It was unclear if he might face more charges.

Jesús Gerardo has the alias “el Kekas,” a which is a slang word for quesadillas. He was arrested along with his partner Ari Gisel García Cota and his brother Cristian Alejandro Garcia.

They were not charged with murder. Andrade Ramírez said: “We are certain that more people were involved.” She said she could not speak about the suspects for fear of prejudicing the case under Mexican law.

Burned truck found by police (
Image:
Facebook/Patrulla 646)

The trio

Callum Robinson’s Instagram account contained the following slogan: “If you’re not living on the edge, you’re taking up too much room.”

Last week, the mother of the missing Australians, Debra Robinson, posted on a local community Facebook page, appealing for help in finding her sons. Robinson said Callum and Jake had not been heard from since April 27. They had booked accommodation in the city of Rosarito, not far from Ensenada.

Callum was a former lacrosse star and moved to the US to pursue a career in the sport in 2013. He played for Stevenson University and won the NCAA’s Division III lacrosse championship, the New York Post reported.

Following his successful college sporting career, Callum played for Australia’s Men’s National Team and joined the Professional Lacrosse League, playing for the Atlas LC team.

His younger brother, Jake, was due to start at a new position in a hospital in Geelong, Victoria, Australia. His parents described him as a "gentle soul."

“It is with heavy hearts that we share the news of the passing of our dear teammate and friend, Callum Robinson,” Callum's former team announced on Facebook. “From his days leading us to victory on the field to his unwavering commitment to academic excellence, Callum was a true inspiration to us all.”

The school added: “With his beautiful long hair and charming smile, he truly embodied the nickname ‘big koala’ — warm, friendly, and always there to lend a helping hand...

“Though he may be gone, Callum’s legacy will live on in our hearts forever. Our thoughts and prayers are with his family and loved ones during this difficult time. Rest easy, Callum. You will be deeply missed, but never forgotten.”

Carter Rhoad worked as an apparel designer in San Diego. Australian Prime Minister Anthony Albanese said on Tuesday he had requested an opportunity to speak to the brothers’ parents Deborah and Martin Robinson.

“This is a terrible tragedy and my heart goes out to them. To identify these wonderful young men and they have been travelling in Mexico. We’ve been dealing with them through the Department of Foreign Affairs and Trade. I’ve indicated that I wish to speak to them at an appropriate time of their choosing,” Albanese told reporters in the Queensland state town of Rockhampton.

Australian Treasurer Jim Chalmers expressed sympathy for the Robinson family. “I think the whole country’s heart goes out to all of their loved ones. It has been an absolutely horrendous, absolutely horrific ordeal and our thoughts are with all of them today,” he said at a news conference Monday in the capital, Canberra.