A 17-year-old boy was rescued by police after his parents left him on the side of a motorway in Cambridgeshire.
The teenager had to walk a mile in the dark to reach an emergency phone when he was left stranded on the M11, police said.
He managed to call authorities, who picked him up and placed him in police protection.
Officers from the Child Abuse Investigation and Safeguarding Unit (CAISU) are investigating the incident.
Cambridgeshire Constabulary said in a statement: “Imagine you are 17 years old. Imagine being left by your parents at the side of a motorway near a city you’re not familiar with.
“Imagine having to walk a mile at night, on the darkest stretch of that motorway, to the emergency SOS phone to get some help.
“That was the reality for one boy recently on the M11. He wasn’t from Cambridgeshire and had no links to here, but he needed our help and we did exactly that.
“Thanks to officers from our Child Abuse Investigation and Safeguarding Unit (CAISU), he was temporarily placed in police protection and is in a safer environment while investigations continue into where he will now be happiest.”
They added anyone with concerns about a child’s safety should report it to police.
All reports can be made in confidence and can be done anonymously.