Mexican attorney general warns MORE suspects will be arrested for the murder of Australian and American surfers who were shot dead in robbery

Authorities are investigating the possible involvement of more suspects in the murder of the three surfers in Mexico, according to the Baja California state attorney general.

María Andrade said law enforcement have zeroed in on an unspecified number of alleged accomplices in connection to the killing of Australian brothers Callum Robison, 33, and Jake Robinson, 30, and their California friend Jack Carter Rhoad, 30, last week in the Pacific coast seaside town of Ensenada.

'We have more people considering that they could have participated in the investigation,' Andrade told Milenio news outlet on Monday. 'I couldn't tell you the number due to secrecy at this time.'

The attorney general's remarks were made just a day after the families identified the bodies of the surfers.

María Andrade, the attorney general for the Pacific coast Mexican state of Baja California, revealed Monday in an interview with Milenio news that authorities have zeroed in on additional suspects linked to the murder of two Australian and one American surfer 

Australian natives Callum and Jake Robison were shot dead along with their California friend Carter Rhoad last week in Baja California, Mexico

30-year-old Californian Jack Carter Rhoad was set to marry his fiancée this summer 

The style of the executions have sparked fears locally about the possible involvement of drug cartels which are rife in the region (pictured: the trio's vehicle was later found burnt-out in the Santo Tomás area)

Their bodies were recovered Friday from a 50 feet deep well near La Bocana Beach, in Santo Tomás, a town in the municipality of Ensenada Each of the victims had bullet wounds on their heads, according to law enforcement.

Jesús 'El Kekas' García, his wife Ari García, and his brother Cristian García, were arrested in an operation Wednesday.

Authorities were able to make the arrests after one the Robison brothers' cell phones was turned on and pinged a local mobile tower.

All three suspects were found in possession of an assortment of methamphetamines and other illegal drugs.

A rescue worker descends into a waterhole where human remains of two Australians and an American were found near La Bocana Beach

The families of Aussie siblings Callum and Jake Robinson confirmed their bodies Sunday

Carter  Rhoad had visited Mexico throughout his adult life after volunteering for a medical mission in Guatemala at 19

The Robinson siblings and Rhoad, who was slated to be married this summer to his fiancée Natalie Wiertz, 32, were supposed to check into an Airbnb in Rosario Beach last weekend after they spent a couple of days camping at La Bocana Beach and last contacted their families April 27.

Andrade said the suspects targeted the surfers because they wanted to steal the pickup truck's tires.

The state prosecutors said that one of the victims got into a struggle with one of the three suspects, who shot him before gunning down the two other men. Their pickup truck was found burned nearby.

Andrade said that the fact that they were in an uninhabited area made them an easy target.

Brothers Jesús Garcia Cota and Cristian García were two of the three arrested. It is unclear which brother is which in their mugshots

Ari García, 23, is one of three suspects arrested. She is reportedly the partner of Jesús Garcia, who was also arrested

Hundreds of people marched through the nearby town of Ensenada on Sunday afternoon, demanding greater security measures amid a welter of cartel-fueled violence (pictured)

'It is a totally remote unpopulated place. There is no communication, no networks, no telephone communication for at least two and a half hours, three inwards,' she explained. 'So, they were very vulnerable. 

'The aggressors knew that they could not ask for help and that in order to later report the theft of the vehicle, it would take them more than three hours to reach (people) or where they could ask for help.

'They saw the opportunity that made it easier for them to commit the crime and that is how they tried to steal the vehicle,' Andrade added. 'There was resistance on the part of one of the young men and later they shot him and later the other two were already upset and also scared by what had happened and what had happened to the first of them and they also tried to defend themselves. 

'However, these suspects had a firearm.'

Andrade also denied various reports that indicated that the three men had been beaten by the suspects.

While some people doubted the robbery motive and suggested it may have been cartel-related, the attorney general stressed all along that the alleged killers were interested in stealing the pickup truck's tires. 

It is believed the region is riven by turf battles between the Sinaloa and Jalisco New Generation cartels, in addition to other groups.

In June last year, the city's mayor, Montserrat Caballero, announced she had decided to live at an army base for her own safety after receiving threats.