As authorities continue searching for the 74-year-old Rancho Cucamonga man missing since May, family members now believe that he was likely kidnapped by someone. 

"He's kind of a guide to my life, for a very long time," said Wen Hou. "I just want my dad back."

His father, Nai Ping Hou was reported missing by family on May 4, but they say things have been different since March, when he became unusually detached in their family group chat. 

"Over time, when I ask if he wants to come meet up with us, you know, I have young children so it's harder for me to travel to him, he would say either he's tired, or 'I'll call you later,' or 'I can't meet,'" Hou said. "But, he's a semi-retired grandpa right now, so that's really strange."

Hou was eventually able to get some friends to check on his father. They stumbled upon a harrowing scene, finding his home of 20 years completely empty and poorly repainted. 

"Not even furnitures or utensils, which is extremely bizarre," Hou said. "That's when I knew, whoever I was talking to was not hte person living at the house."

It was then that they contacted San Bernardino County Sheriff's Department investigators, who recently confirmed that someone was using Nai Ping's phone to impersonate him and made extensive fraudulent transactions with his bank account.

Hou says that on top of all of that, they drained his father's entire retirement savings and used it to purchase gold bars online. 

"Over a $1 million worth of gold bars, which is extremely strange because he has never bought gold in his life," he said. "He's not an online-savvy person."

Hou is though, and it's that role in the cryptocurrency investing world that has him wondering if there's a connection because of it. 

"It's possible, I'm not sure if they looked up my profile," he said. "Typically I would think if you're a big player you would get a ransom."

Family has now set up a where they're offering a $250,000 reward for information that leads to Nai Ping's return or an arrest. They've also hired private investigators to further search efforts. 

Anyone who knows more can contact SBSD at (909) 890-4848 or the family's tip line at (213) 564-9336.