The bodies of an American tourist and two Australian brothers were found in a well in Mexico.
They had all been shot in the head, authorities said.
Australian brothers Jake and Callum Robinson, 30 and 33, and American friend Jack Carter Rhoad, 30, had gone missing in late April.
They were on a surfing trip in Ensenada.
Relatives of the men have identified the bodies.
Police say the men were likely attacked during an attempted theft of their truck.
Baja California state prosecutor Maria Andrade says they were likely shot when they resisted.
Their bodies were dumped in a well a few miles away.
The well seems to have been a dump site for murder victims.
A fourth body was found in the well but is unrelated.
Police say three suspects were arrested.
Although Baja California has fairly high levels of gang-related crime, the Ensenada region is relatively safe.
It is a popular tourist area and cruise port situated just 75 miles from the US-Mexico border.
