The remains of Callum, 33, and Jake Robinson, 30, and their American friend Carter Rhoad, 30, were found in a well, with authorities investigating their deaths as murder.
Mexico Foreign Minister Alicia Barcena offered condolences to the men's parents and her office said it "expresses its solidarity with the families of the victims in the face of this tragic event and deeply regrets the outcome of the events".
Federal Treasurer Jim Chalmers said the identification of the bodies was "frankly horrendous news".
"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," he said.
Bodies found after a search by Mexican authorities have been identified by family members. (HANDOUT/SUPPLIED)
The Robinson brothers, originally from Perth, were in northern Mexico on a surfing holiday when they failed to check into pre-arranged accommodation near the city of Ensenada.
WA Premier Roger Cook said the situation was incredibly sad for the family and friends.
"Everyone from Western Australia is hurting as we hear from more aspects of this story, the violence they were exposed to and of course the loss of life," he said.
Callum was a member of Australia's national lacrosse team and Lacrosse Australia said its thoughts were with the loved ones of all three victims.
"Lacrosse Australia is deeply saddened by the deaths of player Callum Robinson, Callum's brother Jake Robinson and their friend Jack (Carter) Rhoad and send our deepest condolences to their families, friends and teammates," the association posted on Facebook.
About 150 people gathered for a vigil in San Diego where Callum lived, the American ABC network reported.
Callum also played lacrosse at Maryland's Stevenson University and former coach Paul Cantabene said he got along with everyone while being "big, fast, rigid and flat-out just good" on the playing field.
The family had travelled to Baja California state in northern Mexico and were taken to view two bodies found at the bottom of a well.
The remains were found with a third body and a corpse that had likely been there for some time, in the well on a cliff top on Baja Peninsula on Mexico's west coast on Saturday, Australia time.
Baja California state prosecutors said relatives from the two countries had viewed the corpses recovered the remote 15m well.
Thieves apparently killed the three men to steal their truck because they wanted the tyres and then allegedly got rid of the bodies about 6km away.
Three suspects are being held in connection with the case, which locals said was solved far quicker than the disappearances of thousands of Mexicans.
A burnt-out ute was found near where the Robinson brothers and a US friend were camping. (HANDOUT/SUPPLIED)
Baja California prosecutors confirmed last week they were questioning three people.
A criminal charge of forced disappearance, equivalent to kidnapping, was laid against one of the three on Saturday.
Mexican authorities' preliminary hypothesis is that the suspects tried to carjack the trio and the surfers resisted.
They found a burnt-out white ute, believed to be the vehicle in which the men were travelling when they disappeared.
The chief state prosecutor's office said evidence found along with abandoned tents at a burnt-out campsite was linked to the three people being questioned.
Local news outlet Zeta reported the fourth body in the well was believed to be that of the property's missing owner.
with Reuters and AP
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