It's not often drivers stopping at a motorway service station are offered a cup of coffee for free.

But motorists taking a break at Cleckheaton's Hartshead Moor Services on the M62 were offered just that - in a bid to help keep them alive.

Surprised motorists watched as police officers approached them to hand out the coffee as part of a national launch aimed at keeping drivers awake and alert on the road.

The Government's campaign is aimed at alerting motorists to the dangers of driver fatigue.

New research estimates around 10 per cent of all road accidents nationally are sleep-related and on motorways this figure rises to around 20 per cent.

Yesterday's launch was part of the Government's £9 million Think! campaign - which urges people to use roads safely whether driving, walking, cycling or using public transport.

John Jarvis, Government office director of transport for Yorkshire and the Humber, attended the launch at Hartshead.

"We have to get the message across to motorists that driving fatigue is serious and does have an effect on people," he said.

"New research shows that one in 10 accidents on all roads are the consequence of driver tiredness and on the motorway that figure is higher. After a long day's work or a long journey, people are vulnerable to tiredness. Driving late at night and driving in the early hours all makes a difference."

He added: "This scheme is about planning your journey, getting a good night's sleep and taking a break for 15 minutes every two hours. People must recognise the symptoms of feeling tired and if on the motorway, come off at the next service area."

West Yorkshire Police Inspector Brian Pearson, who also attended the launch and spoke to motorists at Hartshead, said driving fatigue was a bigger problem than the police had imagined. "Our main aim is road safety and the prevention of road accidents, but this is a bigger problem than we realised," he said. "Over the last five years 246 accidents in West Yorkshire have been attributed to driver fatigue - eight of those have been fatal accidents and 56 caused serious injury. My main concern is the motorway because people are generally making longer journeys and need to learn to take a break."

Laurence Weston, from Urmston in Manchester, was making a journey to South Milford and had stopped off at Hartshead for a break. "I've always thought taking a break was a good idea," he said. "I usually have the radio blaring and the windows down to keep me alert, but if ever I feel tired I know to take a break. I've been driving for a long time and long distances and I know when to stop.

"It is just not worth the risk to go that bit further," he said.

Research shows that drivers do not fall asleep without experiencing symptoms of tiredness first, so drivers are being urged to treat the onset of tiredness more seriously. The research also showed that in most sleep--related road accidents, the drivers were men and that 50 per cent of the drivers who fell asleep at the wheel were under 30 years old.

Other factors such as the time of day rather than just the duration of driving hours, had a profound effect on driver fatigue. It can set in when travelling in the early hours (midnight to 7am), late at night or following a long working day. The most common time for accidents was between 3am and 8am.

Business drivers are most at risk from driver fatigue, according to the AA, which is calling for employers to be more aware of the dangers their staff face whilst out on the road.

Responding to the Government's campaign, Andrew Howard, AA head of road safety, said: "Business motorists are under pressure to meet deadlines and appointments which means that they often drive too far, too long. As a result they, not holiday drivers, are those who are most likely to suffer from fatigue.

"Company cultures need to change. People must realise that no meeting, deadline or bonus is worth risking a life for. They should set more realistic schedules and be encouraged to stay overnight on long trips."