A Sussex student had a miraculous escape after a 150ft fall on Ben Nevis

Ian Brown, 21, survived for five hours alone on the freezing slopes of Ben Nevis after a friend walked through the night to get help.

Ian, of Mill Road, Lewes, fell as he made his way down Britain's highest mountain on the first day of a hiking trip to the Scottish highlands with colleagues from Lancaster University.

There was speculation last night he had been glissading, an extreme sport where climbers attempt to slide down slopes on plastic bags, but rescuers believe he may just have slipped on ice and shot over the precipice.

His friend placed him in a survival bag and went to seek help.

The friend, a fellow member of the university's hiking club, raised the alarm at a local youth hostel, triggering a major rescue effort by police and the mountain rescue team.

Ian was rescued shortly after 10pm last night and taken by RAF helicopter to a hospital in Fort William where he was treated for a back injury and bruising.

His mother Marie was told of her son's ordeal when he called her late last night.

She said: "He was very shocked and we still don't know much about what happened.

"He just rang to tell us he was in hospital but was OK.

"I spent a sleepless night and rang the hospital first thing this morning to see what they had to say.

"He is bumped and battered and they are keeping him in to have five days of bed rest.

"We are still shaking. We are very thankful it ended this way - somebody up in heaven was watching over him."

Rescuers praised Ian's companion for raising the alarm.

Terry Confield, team leader of the Lochaber mountain rescue team, said: "His colleague made him comfortable, put him in a bag to keep him warm and made sure he had a torch and whistle.

"Unfortunately mobile phone reception is non-existent in that area.

"The helicopter spotted his light and when we got to him he was in good spirits and comfortable.

"It seems to have been an unfortunate accident. I have heard talk of glissading but they did not have ice axes with them and although they may have been tired and decided to slide down on their backsides for a bit, I think he has just slipped.

"We have not had a lot of snow but have had heavy rainfall and I think he slipped on water ice which is very difficult to see.

"His companion did the right thing and made it easy for us to find him. They seemed to have their act together."

Ian, a former pupil of Ringmer Community College, was one of 27 students on a week-long holiday with the university's hiking club.

The second year environmental management student is an experienced hiker who was acting as gear officer for the trip.

A university spokeswoman said: "Members of the hiking club are quite experienced, otherwise we wouldn't send them to Ben Nevis.

"Members are sent on courses every year and on this occasion all the protocols were followed properly.

"The other members of the party were in close proximity the whole time.

"Ian himself is quite experienced as a hiker. He has had to cancel an exam he was taking and will take it in September instead.

"We expect an ambulance will be arranged to bring him back home on Friday."

A police spokeswoman said Ian's companion had done all the right things.

She said: "We would always advise anyone in that situation to make sure the injured person they are leaving is kept warm and has provisions, but then they are better going for help because there is no point both just waiting to be rescued in those conditions."