Search Ends for 21-Year-Old Man with Autism Who Left Home Without Jacket or Phone

• Jonathan Hoang's family reported him missing on March 31
• Despite more than 4,000 total manhours devoted to the search spanning six days, Hoang has still not been found, according to authorities
• "Each day he’s been missing has been indescribably painful for our family," the 21-year-old man's family said

Authorities in Washington state announced they are suspending the ground search for a 21-year-old man with autism while asking the public for information on his whereabouts. 

Jonathan Hoang was last seen at his residence in Arlington, Wash., around 7:30 p.m., local time, on March 30, the Snohomish County Sheriff's Office said in a news release. 

A relative said they possibly heard him leave the home around 5:30 a.m. on March 31, but it may have occurred before that time, authorities added. He was reported missing that same day. 

“Jonathan has autism and he left the house without his cell phone and without a jacket,” authorities said. “He left with his wi-fi only iPad; it does not have cellular data.”

A search for Hoang began and culminated into a full-scale operation on Saturday, April 5, the sheriff’s office continued. About 150 volunteers, ground teams, K-9 units, drones, and the agency's helicopter were involved in the search. 

But despite more than 4,000 total manhours devoted to the search spanning six days, Hoang has still not been found, authorities said. They said an analysis of Hoang’s cell phone contained "nothing of evidentiary value." 

“At this time, the ground search has been suspended, pending any further tips, evidence recovery, or additional leads,” the sheriff’s office said. “[Search and rescue] will continue to do periodic checks in the area and will follow up on all leads.”

Officials added that Hoang is still listed as a missing endangered person. There is no evidence of foul play or him being taken against his will. 

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But in a Wednesday, April 9, Facebook post from a group devoted to the search for Hoang, his family wrote they are begging authorities to look into the possibility that Hoang may have been taken or kidnapped, “as SAR was unable to find any sign of him at all in the woods or on foot.” 

"He is not a child, but he is a disabled adult,” the family said. “Those who knew him well, his family, teachers, doctor, and neighbors know and have agreed he was not prone to wandering and all the circumstances surrounding his disappearance should be cause for alarm.”

“Each day he’s been missing has been indescribably painful for our family,” they added. “He is gentle, kind, funny, and so loved. Please help us find him.”

The sheriff’s office said in its statement that Hoang is high functioning and takes public transit with his job coach and "has been working with his adult transitions program to gain skills for a job in Everett.”

In an interview with NBC affiliate KING, his family said that he may have trouble finding his way back home, adding that he has difficulty with problem solving and shuts down during stressful situations. 

His father, Thao Hoang, said Jonathan wasn’t in his room the morning he disappeared when his mother checked on him. 

“Maybe he got out, for whatever reason was prompted, but somebody might have lured him out, or somebody might’ve asked him for help and got him out of the house in a panic situation," he told KING. "He disappeared that way, trying to help somebody?”

The sheriff’s office said anyone who has seen Hoang or information on his whereabouts should immediately call 911.