Scott Diver, 16, has been away from his home in Clydebank since Saturday September 17.
Children Warned Against Playing On Rails
Rail safety officers have issued a warning to young people across Scotland as reports of children playing on the tracks increase.
The number of children reported to have gone on to railway lines in the summer has jumped by 18% between 2013 and 2015.
British Transport Police say figures indicate young people are twice as likely to do so at this time of year than in the winter.
Officers stress playing on or taking a shortcut over railway lines can kill and are stepping up patrols across the country.
They are urging parents to warn children of the dangers of playing on the tracks.
In the past decade, nearly 170 young people have been killed on railway tracks across Britain, just under half of whom were aged under 25.
About two-thirds (72%) were hit by a train, 17% were electrocuted and others fell from structures or trains.
Chief Inspector Dave Marshall said: "The last thing our officers want to do is knock on someone's door to tell a parent their child has been killed or seriously injured as a result of trespassing.
"We're doing all we can to keep young people safe by patrolling areas where we know they're likely to trespass and prevent them from doing so. However, we cover thousands of miles of track and we cannot tackle this issue alone.
"That is why we are urging parents and young people to heed this warning and take a reality check when it comes to trespass. It's not a game: they are real tracks, with real trains and real-life consequences.''
Glasgow has the highest rate of people venturing on to train lines in Scotland, with 50 incidents in 2015, up from 39 the previous year.
Edinburgh's rate remained steady at 27 incidents each year while Kilwinning in North Ayrshire recorded the third highest rate in Scotland at 23 in 2015, up from 13 the previous year.
St Andrews University came out on top in the latest guide from The Times newspaper.
A former detective is calling on the convicted murder to confess the rest of his crimes.
Police found a woman's body in a Govanhill flat yesterday.
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