NEW YORK (CBSNewYork) — A mother and father in the Bronx are desperately searching for their 13-year-old autistic son who has hasn’t been seen since he left for school Tuesday morning.

For the past two days, Rosura Tabers has been worried sick about her son, Ross Harrison. She said he ran out of the building on West 182nd Street on Tuesday morning after complaining about being bullied.

“That day, he told me he don’t want to go to school because someone was going to hit him on the bus,” she told CBS 2’s John Schriffen.

As the two started to head down from the fifth floor to the school bus, relatives said Harrison ran out the door and kept going. The family said the building’s super saw him take off down the block.

“He’s only 13 and he cannot defend himself,” Tabers said. “That’s what I worry about, that somebody might hurt him.”

His father, also named Ross Harrison, handed out flyers all day and night Thursday hoping that someone has seen his son.

“I’m stressed out because he has autism,” he said. “He can basically communicate and he can say his name, but I don’t know how he has been making it without no food or water.

“I’m scared, I’m scared but I’m keeping hope alive. I would never even wish this on my worst enemy.”

Shaakira McFarlande told Schriffen she saw the missing boy riding the subway, but didn’t realize who he was until watching CBS 2 News at Noon.

“I started screaming ‘that’s the boy who was sitting next to me on the train on Tuesday,'” McFarlande said. “He was on the train pacing back and forth, moving from seat to seat.”

McFarlande said he was on the uptown 2 train in the Bronx around 10:30, just a few hours after Harrison was reported missing.

“He asked the man who was selling books on the train if he could see a book and the man told him no. So he started cursing. Then that’s when he got off at 174th,” McFarlande said.

Because of that possible sighting, the family’s search expanded to the subway, where Thursday night Harrison’s sister and uncle scoured platforms and trains, reported CBS 2’s Sean Hennessey.

“I try not to cry, but it’s hard. You’re thinking if he has an aide, where is he sleeping?” Hilda Harrison said.

The theory the family members are going on is Ross is getting on and off subway stops because “he’s trying to locate his stop,” said Juan Tavares, the boy’s uncle. “He’s trying to go home. He’s trying to go back home.”

Home is where loved ones were keeping vigil and where police were checking in, all hoping to find this moving needle in a huge haystack.

“That’s exactly what it is. You can’t, New York is so big and so vast and the subway systems are so long that you can get lost,” the boy’s father said.

The family is pleading to the public for help.

“Hold him and call the police until we can get there and don’t try to get him because he don’t do nothing to nobody,” Tabers said.

The 13-year-old was wearing a black sweater, black shirt, black pants and brown sneakers when he went missing.

Anyone with information on where he might be should call police or Crime Stoppers at 1-800-577-TIPS (8477) or visit www.nypdcrimestoppers.com.

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