A woman and two males have has been arrested during the search for two missing Perth brothers in Mexico that failed to return to their Airbnb after a surfing trip.
Jake and Callum Robinson went missing five days ago in the Baja California region near Ensenada on Mexico's north-west coast.
After sharing regular social media posts about the first two days of their trip, they have not been heard from since Saturday.
Local media reports indicate that a 25-year-old woman has been arrested in connection to the case. She was discovered in possession of a mobile phone belonging to one of the brothers, along with methamphetamine.
Two males were also arrested alongside her.
Earlier, the pair's mother Debra Robinson issued an urgent plea for help to find her sons.
Jake and Callum Robinson have not been heard from for days after going on a surfing trip to Mexico (pictured with their parents)
Debra Robinson appealed for help from the public in the search for her sons on social media on Thursday
'Reaching out to anyone who has seen my two sons,' Ms Robinson wrote on Facebook.
'They are travelling with another friend, an American citizen.
'They were due to book into an Airbnb in Rosarito after their camping weekend but they did not show up.'
Ms Robinson posted a photo which said her sons had gone missing around the Rosarito and Ensenada region of Baja California on Saturday morning.
Rosarito is a coastal city in Baja California, Mexico and is about an hour's drive north of Ensenada and a 45 minute drive south of the US city of San Diego.
It said they were driving a Chevrolet Colorado with the Californian number plate 70189W1.
Ms Robinson said there was a medical concern, given Callum is a type one diabetic.
She asked for anyone who had seen her sons or knew their whereabouts to contact her.
Lacrosse Australia issued a statement on social media expressing its concern over the whereabouts of Jake, Callum and their friend, Jack Carter Rhoad.
It described Callum as an 'Australian lacrosse star'.
A woman has reportedly been arrested during the search after she turned on a mobile phone that belonged to one of the brothers (pictured with their parents)
Jake and Callum are understood to have gone missing from the Baja California region near Ensenada
'We urge the Australian lacrosse community and our global lacrosse family to continue sharing the post from Callum's friends and family (located on the LA Facebook and Instagram story) in the hope that Callum, Jake and Jack are found safe and sound,' it said.
'Our thoughts are with the families and friends of the Callum, Jake and Jack during this incredibly stressful time.'
WA Premier Roger Cook said the situation was 'very worrying'.
'When we do send our young men and women overseas to enjoy that adventure holiday, they invite an element of risk and this is really quite distressing,' he told reporters.
'I understand that one of the individuals has a medical condition that would need ongoing care, so I share concerns of all Western Australians in terms of their welfare.'
The Department of Foreign Affairs and Trade confirmed they were assisting the family.
'The Department of Foreign Affairs and Trade is providing consular assistance to the family of two Australians reported missing in Mexico,' a spokesperson said.
'Owing to our privacy obligations we are unable to provide further comment.'