Why Were the 3 Missing Surfers Killed in Mexico? What We Know So Far

Authorities are investigating how the three ended up dead in the bottom of a well, and who killed them

The American from San Diego and his two friends — brothers from Australia — were living the dream, surfing and camping along the sun-kissed Mexican coast.

Callum Robinson, 33, posted pictures from the trip on Instagram of him, his brother Jake Robinson, 30, and their American friend, Jack Carter Rhoad, also 30,  relaxing in a jacuzzi, eating tacos and drinking beers with their feet up.

That was before the unthinkable happened.

On Friday, FBI San Diego announced that Rhoad, of San Diego, and Jake Robinson, of Perth, Callum Robinson, also of San Diego, were found dead in the bottom of a 50-foot well in a remote part of Santo Tomas, Baja California, NBC San Diego reports.

They had all been shot, authorities said.

The friends were last seen on April 27 while they were surfing and camping out along the Mexican coast, south of Ensenada.

They pitched tents and parked their white pickup truck nearby so they could surf the cerulean waves.

But they weren't out there alone.

"The attackers drove by in their vehicle," Baja California’s chief state prosecutor María Elena Andrade Ramírez said at a press conference Sunday, CBS News reports.

"They approached, with the intention of stealing their vehicle and taking the tires and other parts to put them on the older-model pickup they were driving,” she said.

Related: One of the Surfers Killed in Mexico Was Engaged to Be Married In August

"When they [the victims] came up and caught them, surely, they resisted," she said.

"And these people, the assailants, took out a gun and first they killed the one who was putting up resistance against the vehicle theft, and then others came along and joined the fight to defend their property and their companion who had been attacked, and they killed them too," she said.

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Investigators found a cartridge casing, plastic gallon bottles, blood stains and drag marks in the area where the three men had set up camp, authorities said, CBS News reports.

Related: Authorities Reveal How Missing Surfers from U.S. and Australia Found at Bottom of Well in Mexico Died

The assailants burned the tents, authorities said.

Authorities also found a burned-out white pickup truck they believe belongs to Callum Robinson, CNN reports.

Police arrested Jesus Gerardo, whose alias is “el Kekas” and who has a criminal record, in connection with the case, CNN reports. It's not clear if he has retained an attorney to comment on his behalf.

They are questioning others, including a man and a woman who could be "directly or indirectly related to this case," Andrade Ramírez said, according to CBS News.

Authorities are still investigating.

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