WINCHESTER — It has been nearly four months since Maryland resident Jason Diego Abarca went missing after allegedly carjacking a vehicle in Winchester, and his mother now suspects he may have been murdered.

"I know my son is dead," a distraught Jennifer Soto of Hagerstown, Maryland, said on Monday during a phone interview. "He would have called me the very first day, or the second. He has never called me."

Winchester Police Chief Amanda Behan could not offer specific details regarding the ongoing Abarca case, but she said the investigation is active and that the U.S. Marshal's Service is now involved. She declined to elaborate on the federal law enforcement agency's role in the situation.

Abarca, 19, of Hagerstown, has not been seen since Dec. 13, when he allegedly carjacked a vehicle in the McDonald's parking lot at 1124 Berryville Ave. in Winchester. A media release from the Winchester Police Department states a man with a knife ran up to the vehicle, made the driver get out and stole her car.

Soto has said she is not questioning her son's guilt or innocence, but insists his actions on Dec. 13 were the result of a mental breakdown brought on by the May 24 suicide of his brother, Army Capt. Korey Decarlos Platt, coupled with a possible overdose of the Adderall he was prescribed for his attention-deficit/hyperactivity disorder.

Using too much Adderall can make a patient experience hallucinations, delusions and paranoia, and Soto believes that's what was happening with her son when he left his home in Hagerstown driving an SUV he had been renting.

According to police reports and information from his mother, Abarca crashed the SUV around 3:30 p.m. Dec. 13 on the Interstate 81 South off-ramp to Berryville Avenue in Winchester.

At 3:39 p.m., police received a report of someone matching Abarca's description who was carrying a knife and attempting to carjack a vehicle near Berryville Avenue. Soto said her son apparently took two of her kitchen knives before he left the house.

The suspect ran when police arrived, but at 4:02 p.m., Abarca allegedly carjacked a vehicle in the nearby McDonald's parking lot. A media release from the Winchester Police Department states a man with a knife ran up to the vehicle, made the driver get out and stole her car.

No one was hurt in either incident.

That evening, the stolen car crashed on a straight stretch of Star Tannery Road near Star Tannery, close to the Frederick County/Shenandoah County border. The driver left the vehicle.

A short time later, a K9 unit from the Frederick County Sheriff's Office tracked the suspect's scent from the crashed car to the side of the road, where the trail ended.

Despite exhaustive search efforts in Star Tannery that continued into January, Abarca is still missing and investigators are trying to determine what happened to him.

"I have nightmares," Soto said. "I'm depressed and I'm trying to keep things together, but I'm not making things up in my mind."

Soto said she first thought her son must have frozen to death in the mountains of Star Tannery, but she has since learned things that make her suspect Abarca was a victim of foul play.

While there is currently no direct evidence indicating that Abarca was murdered or is dead, Soto said a Shenandoah County Sheriff's Office incident report indicates that four people apparently chased after her son when he sped away from the McDonald's in Winchester, and one of them supposedly called a police dispatcher and said he had a gun and wasn't afraid to use it.

"They saw him [Abarca] have the knife, scare the lady [who owned the vehicle] and take her car, and then they immediately started chasing after him," Soto said of the four rumored pursuers.

She said police photos of the stolen car that crashed in Star Tannery have not been publicly released, but they clearly show that the car sustained significant damage to its rear. Soto said she believes it is proof the four individuals rammed into the back of the car and forced it off the road.

"When you see that car that he wrecked, it looks literally like someone smashed into the back of him," she said. "But when I asked that of the police, they said, 'Oh no, he just ran into some trees.'"

Soto also claims that investigators never reviewed footage from a surveillance camera that was mounted on the Star Tannery property where the stolen car crashed. Instead, police took the property owner's word that Abarca was not seen in the video.

"They didn't ask for the actual camera footage," Soto maintains.

On top of all this, the mysterious involvement of the U.S. Marshal's Service has Soto wondering why it's now part of the search for Abarca. According to Soto, marshals showed up at her other son's home in Maryland two weeks ago and followed his fiancée when she drove to work.

"U.S. marshals surrounded her car with guns and had the sniper red dots on her forehead for no reason," Soto said. "Jason's not hiding there."

Behan would not comment on the U.S. Marshal's Service's role in the case, or if the alleged incident with the fiancée was related to Abarca's disappearance.

Soto said she and the rest of her family are eager to hear from anyone with information about the alleged carjacking, chase and crash.

"Maybe someone saw what happened. Maybe someone was involved but didn't want to be involved and they have a guilty conscience," Soto said. "If someone murdered my son, of course I want justice. But I need to find my son's body and give him rest."

If you have information about the disappearance of Jason Diego Abarca and want to remain anonymous, contact Crime Solvers at 540-665-TIPS (8477) or via the P3 app for Apple and Android smartphones.

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