SCOTTSDALE, Ariz. (NewsNation Now) — The family of Najib Monsif is asking for the public’s help finding the 20-year-old with autism after he disappeared from his home in Scottsdale more than two weeks ago. They say he has the mental capacity of an 8-year-old child.

Najib’s family describes him as innocent and vulnerable. They fear he’s fallen into the wrong hands, either meeting someone while playing video games or when he wandered off.

Josie Monsif, Najib’s sister, told NewsNation’s Marni Hughes that she is convinced he has been kidnapped.

“The worst thing to say would be his body would have been found by now nearby,” Josie Monsif said. “He’s out there somewhere and he’s just not alone.”

Najib left behind his cellphone and doesn’t drive, so his family says he couldn’t have made it far on foot.

“If you see him, please under no circumstance leave him alone,” said Josie Monsif said. “Stay with him and call police immediately.”

His dad was the last person to see him between 2 a.m. and 3 a.m. Sept. 23.

“The day before he disappeared, he said to my brother while he’s playing video games with him on live, that he would never see him again,” Josie Monsif said. “And he kind of waved it off and the next morning he was gone.”

Authorities in Scottsdale and Maricopa County are actively looking for Najib, along with a community of supporters.

“We’ve gone door to door to ask neighbors if they saw anything,” said Scottsdale police Officer Aaron Bolin. “There was also a video canvas of the neighborhood and surrounding businesses to look for any surveillance video that could compliment our search for Najib. The canal and the desert area north of there was searched by bicycle, drone and by air unit … also used search dogs to get an idea of where he was last seen in a neighboring business complex.”

The dogs put his last known location at an Albertson’s grocery store not far from his house. From there, he seems to have vanished without a trace.

Najib often goes by the name Jubi. His family says he walks with a noticeable shuffle and has never wandered off before.

“He rarely leaves the house,” Josie Monsif said. “He doesn’t like leaving the house. This is very, very abnormal.”

Najib is about 5 feet, 10 inches tall with a thin build and is possibly wearing all black clothing.

Josie says she wants Jubi to know, “We’re not gonna stop looking.”

She also has a message for whoever may have possibly taken him.

“My brother is very loved,” Josie said. “And my family is committed to getting him back. If you can find the kindness in your heart to help us find him, or come forward or if you know anything, please call the Scottsdale police. And if you don’t, you know your road will come to an end eventually, because we’re not going to stop.”

Anyone with information is asked to contact the Scottsdale Police Department at 480-312-5000.

See Josie Monsif’s full interview with NewsNation Prime Monday night in the player below.

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