Eerie surveillance footage of a missing 13-year-old girl has shown her walking with an unknown person at a train station before she vanished without a trace.

Natalie Armstrong was last seen exiting a Dallas Area Rapid Transit (DART) train with a mysterious person at SMU/Mockingbird Station around 8.43pm in Dallas, Texas on October 21 after she has been reported missing for nearly a week.

‘Natalie is described as a 13-year-old girl, standing 5′ 3″ tall, weighing 135 pounds, with brown hair and hazel eyes. She was last seen wearing a gray hoodie, blue jeans and white shoes,’ the Dallas Police Department wrote in a Facebook statement.

According to police, Armstrong was later seen on the 9300 block of Whistle Stop Place around 10.08pm on that same day.

Megan Bernhardt, Armstrong’s mother, told NBC 5 that Armstrong had been diagnosed with autism and is on the spectrum. Her mother stated she was experiencing school evaluations that may have been a trigger before she ran away.

‘She gets very overwhelmed easily… She’s also dealing with some anxiety and depression,’ Bernhardt told the outlet.

‘She ran away from home in Lake Highlands on Wednesday night around 8:30pm…She is at risk of medical complications that could be life-threatening without her daily meds,’ Bernhardt wrote in a Facebook statement.

Police officials released photos of railroad surveillance footage that shows Armstrong walking with an unidentified person along the train platform.

Natalie Armstrong was last seen exiting a Dallas Area Rapid Transit (DART) train with a mysterious person at SMU/Mockingbird Station around 8.43pm in Dallas, Texas on October 21 after she has been reported missing for nearly a week

Police officials released photos of railroad surveillance footage that shows Armstrong walking with an unknown person along the train platform. They have not identified him at this time but noted he could be another minor

The Dallas Police Department reported Armstrong: ‘standing 5′ 3″ tall, weighing 135 pounds, with brown hair and hazel eyes. She was last seen wearing a gray hoodie, blue jeans and white shoes’

They have not identified the person at this time but noted they could be another minor.

‘Officers are still out looking for Natalie and have been since we pushed out the ᑕriᩚtiᩚcal missing information over the weekend,’ the Dallas Police Department confirmed to the Daily Mail in a statement.

Since Armstrong ran away from home, Bernhardt has posted a Facebook video, alongside Alfonso Solis, a search and rescue volunteer, pleading to the public and local communities to help find her daughter.

Solis has founded Send Me DFW, a community organization that specializes in search and rescue for missing persons.

‘We know she is on foot. We know that she does know the DART rail system. If you live in a 75231 zip code, just look outside your window and see if you see this little girl. She is 13-years-old. If you have a yard or a shed, just check your shed. Make sure she is not in there,’ Solis said.

The volunteer noted that Armstrong has family in the Farmersville and Grapevine areas in Texas.

Solis said the child has had ‘no phone, no social circle, and no social media activity’ since she ran away from home.

He confirmed he has worked together with authorities to find the young girl and bring her home safe.

According to police, Armstrong was later seen on the 9300 block of Whistle Stop Place in Dallas, Texas around 10.08pm after leaving the DART train station (pictured), that same day

Since Armstrong ran away from home, Megan Bernhardt, (right) her mother, has posted a Facebook video, alongside Alfonso Solis, (left) a search and rescue volunteer, pleading to the public and local communities to help find her daughter.

Solis said the child has had ‘no phone, no social circle, and no social media activity’ since she ran away from home and was seen by the DART station (pictured) in Dallas, Texas

According to police officials, anyone with information on Natalie’s whereabouts has been asked to contact the Dallas Police Department directly or Dallas Police Youth Operations/Missing Persons Unit at 214-671-4268.

They have asked the public to ‘please reference case number 155505-2026.’

The Daily Mail has reached out to DART Police Department for comments or additional details on Armstrong’s disappearance.