(CNN) -- On Tuesday, police identified a third person detained as a witness in connection with what authorities believe was the drug-related abduction last week of a 6-year-old Nevada boy, who was found safe three days later.
Jose Lopez-Buelna, 48, was arrested Friday as police were serving a search warrant at a home in Las Vegas, Nevada, police said in a statement released Tuesday.
The warrant was associated with the abduction of Cole Puffinburger, snatched October 15 from his Las Vegas home. Police said at least two of three armed suspects entered the boy's home, tied up his mother and her fiance, and ransacked the home, leaving with Cole when no money was found.
Cole was missing for three days before a bus driver spotted him walking on a sidewalk in east Las Vegas. He was reunited with his mother after undergoing medical checks.
The boy's grandfather, Clemens Fred Tinnemeyer, 51, and his companion, 42-year-old Terri Leavy, were detained Monday as witnesses.
The two were arrested in California on federal material witness warrants, and a federal judge on Monday ordered them returned to Las Vegas in the custody of U.S. marshals for questioning in the case.
Authorities have focused on possible drug links in Cole's abduction. Police said earlier that Cole was kidnapped by drug dealers attempting to recover lost money and property. Watch how kidnapping exposes a growing trend »
Citing sources and police, the Las Vegas Review-Journal newspaper has reported Tinnemeyer may have stolen millions from a Mexican drug cartel.
Police previously said Tinnemeyer was involved in "significant" drug dealing involving millions of dollars, but have not said publicly whether they believe he was involved in the drug operation, what role he may have played or whether the child's abductors were seeking a ransom. Officer Cris Johnson told the newspaper methamphetamines was believed involved.
When the boy was found, "he was in good shape, he was extremely healthy," said Las Vegas police Capt. Vince Cannito. He said that while the investigation initially focused on kidnapping, now it's centered around drug dealing and possible extortion.
The boy's abduction triggered a massive search for him and received national attention.
Actions connected to the case in several jurisdictions have resulted in a large amount of cash and evidence being recovered, Cannito has said.
Lopez-Buelna faces charges of possessing a firearm as a convicted felon. He "has declined any and all media interviews," the statement said.
Police have also said a man named Jesus Gastelum, who also goes by the name Ferdinand Gastelum, is sought for questioning in the case.