• The killings have sparked fear and anger in Baja California.
• It is one of Mexico's most violent states, as local drug gangs fight turf wars.
Image: Instagram/@Callum10Robinson
A man charged over the disappearance of three tourists on a surfing trip in Mexico confessed to killing them, a court has heard.
Australian brothers Jake and Callum Robinson and their American friend Jack Carter Rhoad disappeared on 27 April near Ensenada.
Jesús Gerardo on Wednesday faced court on kidnapping offences, but officials say murder charges will soon be laid.
Also known as "El Kekas", he is yet to enter a plea.
Baja California state officials have said the three tourists - all in their early 30s - were probably killed while trying to stop the tyres of their pickup truck being stolen.
Their bodies were found dumped in a cliffside well six days after they disappeared, each with a gunshot to the head, according to local authorities. A fourth body was also found in the well but had been there longer and was unconnected to the case, they added.
Jesús has been charged with "forced disappearance" and his girlfriend Ari Gisel and another man have been detained for their suspected involvement. Their surnames have been suppressed by the courts.
During Wednesday's court appearance, prosecutors named Ari - who has not been charged over their disappearance - as one of their witnesses.
The court heard the 23-year-old told investigators Jesús had turned up at her house on 28 April, telling her he had done something to "three gringos".
She asked what he meant, to which he replied "I killed them", the hearing was told.
He then showed her he had fitted out her car with new tyres, that were allegedly stolen from the slain surfers, prosecutors alleged.
They also told the court they believed other people were involved in the killings.
Earlier this week, Jake and Callum Robinson's parents travelled from Perth to Mexico to identify their bodies.
In an emotional tribute on Tuesday, Debra Robinson said: "Now it's time to bring them home to family and friends and the ocean waves in Australia."
The killings have sparked fear and anger in Baja California.
It is one of Mexico's most violent states, as local drug gangs fight turf wars.
But the Ensenada area, about 120km (75 miles) south of the US-Mexico border and known for its surfing conditions, is considered safer and has long attracted tourists from California.
Scores of protesters marched through the city on Sunday, carrying surfboards plastered with slogans demanding safe beaches.
A group of surfers later performed a "paddle-out" ceremony, an ocean vigil to honour the trio.