Darren Mack, 45, was believed to be on Mexico's west coast and had been spotted in the Puerto Vallarta and Cabo San Lucas areas, Reno Police Chief Michael Poehlman said.
His plan to turn himself in at the U.S. consulate in Puerto Vallarta had been the most significant break in an international manhunt for Mack since the attacks on Charla Mack and Judge Chuck Weller.
The former pawn shop owner is charged with the murder of his estranged wife, whose body was found in a pool of blood in his town house garage on June 12, hours after Weller was shot in the chest while standing by the window of his courthouse office. No charge has been filed yet in the attack on Weller, who survived.
Mack contacted Washoe County District Attorney Dick Gammick earlier this week and "expressed a desire to surrender," Poehlman said at a news conference Thursday.
Gammick said that Mack sounded "concerned" and that he thought Mack was being "pretty straight up" when arranging the plan.
The chief said investigators last communicated with Mack on Wednesday, and they believed he was in Mexico based on comments he made and information the FBI developed.
"He would not tell me where he was," Gammick said.
Mack also asked Gammick to call his family "to give his love to his mother and brother and tell them he was in good health," Gammick said.
Officers who searched the townhouse found boxes of ammunition and an empty gun case with a receipt for a Bushmaster .223-caliber rifle equipped with a laser sighting device.