It is thought that the teenage boy who was killed by a train last night may have ran across the track as he fled from a gang of youths.
Fifteen-year-old Ryan Quinn from Coleraine, Co Antrim was struck on the nearby Portstewart to Portrush line late last night. He died at the scene.
Police are treating the death, which was reported at 11pm, as suspicious.
It is understood that shortly before the fatal incident he was being chased by a group of teenagers following an altercation in a licensed premises.
The line remains closed as examinations are carried out.
Assembly member for the area John Dallat described the incident as “a tragedy almost beyond belief”.
“It seems the boy was fleeing some kind of incident, escaping along a narrow lane that leads up to the Portrush-Coleraine railway,” said the SDLP representative.
“My deepest sympathy goes to the family of the young boy. I pray that they may have the strength to cope with what happened. The PSNI major incidents team is in Coleraine trying to piece together the events leading up to the death.”
Fellow MLA David McClarty said he was stunned by the death.
“To wake up to this news this morning is just numbing,” said the Ulster Unionist. “For a boy to lose his life like this is just terrible.”
Portstewart councillor Bernard Fitzpatrick said the community was reeling after the tragedy.
“For this young man to lose his life in this way is absolutely tragic,” said the Alliance party representative.
“Everyone is totally shocked. My sympathies are with his family at this difficult time.”
A spokeswoman for train operator Translink said the company was assisting the police with the investigation.
“We can confirm there was an incident on the Derry line at approximately 11pm last night where a young man died,” she said.
“We extend our sympathies and condolences to the young man’s family.”
Police have appealed for witnesses to come forward.