John Storrie, 18, went missing in Glasgow on Tuesday evening during a downpour which led to major flooding in parts of the city.

His family said they were "stunned" by the freak accident - but remaining positive.

There are people whose names we will never know but whose conduct throughout this difficult period will remain a constant source of comfort to us all

Family statement

And in a statement issued through Strathclyde Police, the family said: "We have been overwhelmed by the scale of the efforts being directed at returning John to us.

"We have come to trust the judgement and professionalism of the many hundreds of rescue workers who have been involved and, indeed, are humbled by the many courageous and selfless acts we have witnessed.

"There are people whose names we will never know but whose conduct throughout this difficult period will remain a constant source of comfort to us all."

Mr Storrie was walking his dog in Riddrie Cemetery on Tuesday evening when a hole appeared in the rain sodden ground.

One witness said she had heard cries for help and seen a head sticking out of a hole.

It is believed that the teenager was swept away into the old mine tunnels underneath the cemetery.

Air pocket

The search operation, which has been continuing since Tuesday evening, resumed again on Saturday morning.

The rescue team has been using drawings of the area dating back to 1891 to help in the search.

Rescuers have not given up hope of finding Mr Storrie alive, saying that he could be trapped in an air pocket.

In the statement, his family said they had been stunned by the accident.

But they added: "Whatever the outcome, for now, we remain positive."