One of the suspects in the slaying of three surfers on Mexico's Pacific coast confessed to his girlfriend that he killed the three "gringos" last month, according to a report. 

The suspect, identified as Jesus Gerardo Garcia Cota, appeared in court on Wednesday on kidnapping charges, the 1News reported.

 He did not enter a plea and is expected to be charged with murder, officials told the outlet.

The three - Australian brothers Jake and Callum Robinson, and American Jack Carter Rhoad - were believed killed by a group of men trying to steal the tires on their truck in the popular but remote surfing spot near Ensenada on Mexico's Baja California peninsula. 

They went missing on April 27.

At the hearing in Mexico, Ari Gisel, the suspect's girlfriend, said he showed up at her house on April 28 and said he "f---ed up three gringos."

The 23-year-old Gisel asked what Garcia Cota meant. 

He replied, "I killed them."

Garcia Cota, also known as "El Kekas," slang for quesadillas, then showed her his car with new tires that prosecutors said were taken from the three surfers. 

Prosecutors say Garcia Cota and two others robbed the three men of the tires, cash and electronics. 

"While the foreigners were camping, they were surprised by Jesús, and other people, with the intention of stealing their vehicle and in response to the victims' reaction, they deprived them of their lives," Baja California's Attorney General María Elena Andrade Ramírez said.

The bodies of the three men were found in a well six days after they disappeared with gunshot wounds to their heads.