RENO (CBS/AP) -- The FBI has joined an investigation into four killings in northern Nevada that may be linked, including the former president of the Reno Rodeo and his wife who authorities said were shot to death in their home earlier this week.
Washoe County Sheriff Darin Balaam on Friday identified the latest victims as Gerald David, 81, and Sharon David, 80. Their bodies were discovered at about 4 p.m. Wednesday on the south edge of town.
Balaam said the fact they were killed with a firearm is "an additional similarity" to a pair of Douglas County homicides within the past 10 days in Gardnerville, south of Carson City. He said earlier that all four victims were elderly and items were taken from their homes.
"However, we are still unable to confirm an absolute connection," he said Friday.
"Our thoughts and prayers go out to the families of the victims. As these cases develop, law enforcement will continue with our regional collaborative effort aimed at increasing the safety of the public while we work toward bringing those responsible for these crimes to justice," the sheriff told CBS Reno affiliate KTVN.
Gerald David was the president of the Reno Rodeo in 2006 and Sharon David, who went by Sherri, was an active member of the Rodeo Association, according to the Reno Gazette Journal .
Balaam said Thursday that the Douglas County and Carson City sheriff's offices, along with Reno and Sparks police, were working to determine "what, if any connection, there may be" in the four homicides. At that time the official cause of death of the Reno victims had not been determined.
Authorities are offering a $10,000 reward for information leading to an arrest.
In Gardnerville, Connie Koontz, 56, was murdered Jan. 9 or 10 in her home, authorities said. Sophia Renken, 74, was found dead in her home about a mile away on Jan. 13.
"This is an active investigation in the very early stages," Balaam said Thursday. "As we work to learn more, we want to address the very real and legitimate concerns of our communities. ... This case is our top priority."
The sheriff urged residents to turn on outside lights, secure their homes and refuse to open the door for anyone they don't know.
"Stay alert for any suspicious activity and report it immediately to law enforcement," he said.
© 2019 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report
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