A massive rescue operation involving the Swiss army, police and emergency services was mounted in the world's second-biggest road tunnel, after a collision caused an inferno, killing at least 10 people, and it is feared the toll will rise.

A massive rescue operation involving the Swiss army, police and emergency services was mounted in the world's second-biggest road tunnel, after a collision caused an inferno, killing at least 10 people, and it is feared the toll will rise.

The police have a missing person's list with 80 names on it, although they insist that the death toll is unlikely to rise that high. The list is based on people reported missing by family and friends. No firm figure for the anticipated number of casualties has been given, although authorities said it could be around 20.

The fire erupted a mile from the southern end of the 10-mile Gotthard tunnel, the main route connecting northern Europe with Italy. Police said two lorries travelling in opposite directions collided head on, igniting the tyres and plastic which one of them carried. One of the lorry drivers survived and other motorists managed to turn or reverse out. Police arriving from the northern end helped turn trapped vehicles around but many motorists just got out and ran.

Under the intense heat, the roof of the single-bore tunnel caved in along a 300-metre section. Although the accident was a mile from the southern exit, rescuers organised the evacuation from the northern end, because they could not get in.

The survivor, Bruno Saba, said he was heading south when he saw the other lorry go out of control, smash into his vehicle and slam into the tunnel wall, trapping its driver in his cab. "I was able to climb out and help other people escape," said Mr Saba. Another driver, Marco Frischknecht, who was hauling a car transporter, said: "Suddenly there was smoke, and I couldn't see anything. I tried to reverse, but there were so many people I had to give up." He escaped by creeping along the wall and feeling for an opening. "Luckily, I drive there every day, so I knew where the exits were." Mr Frischknecht is in hospital, suffering from shock and smoke inhalation.

Last night, rescue services were still struggling to reach the accident, and warned that the death toll could go up. "Along a 300-metre stretch, we have no idea what's awaiting us," said a spokesman for police in Ticino, the Italian-speaking canton at the tunnel's southern end.

The Gotthard tunnel, built in 1980, is among the most modern in Europe, and won top marks for security in a report by the German motoring organisation ADAC two years ago. Unlike many similar constructions, it has a rescue tunnel running parallel, and escape chambers fitted with fire extinguishers every 250 metres. Fumes filling the tunnel can be replaced with fresh air within 15 minutes. But the report said the rescue shaft is too narrow for fire engines. Yesterday, emergency crews who arrived within minutes of the crash confronted temperatures in excess of 1,000C. "The heat is too high and there is zero visibility," said the Ticino spokesman.

An average of 1,400 lorries or juggernauts, often carrying flammable material, use the Gotthard every day. Since the closure of France's Mont Blanc tunnel two years ago, it has become the most important route through the Alps. Last year alone, an estimated 1.2 million lorries passed through.

But in modern tunnels, accidents are unavoidable. In an average year, there are 44 collisions and five fires. And as the volume of road traffic soars in Europe, its tunnels are becoming death traps. Alpine countries are discussing tunnel security, after disasters in France, Switzerland and Austria.

Firts, the Mont Blanc tunnel was closed in 1999 after a fire that killed 39 people and for which a lorry was also blamed. It has been shut for repairs and refurbishment and is to reopen this year, fitted with the latest life-saving technology.

Two months later, 12 people died in Austria's Tauern tunnel, near Salzburg, when a lorry ploughed into a car, setting off a chain of explosions which destroyed 16 lorries and 24 cars. Many victims choked to death while trying to escape.

Since then, there have been fires in two other Austrian road tunnels and a blaze in the tunnel of the funicular railway at the Austrian ski resort of Kaprun, which killed 155.

Yesterday two Swiss motoring organisations urged their government to build a second road tunnel at the Gotthard to separate traffic in opposite directions. The Gotthard links the towns of Göschen in the north to Ariolo in Ticino. It allows travel from Hamburg to Reggio di Calabria in southern Italy without leaving a motorway. That means avoiding miles of twisting road over the St Gotthard Pass which is closed by snow for up to six months a year. Now, with half-term school holidays under way in parts of western Europe and about to start in Germany and France, traffic heading to Italy is likely to be immense.

The Swiss authorities warned that the Gotthard would probably be closed for days, if not weeks, causing holiday chaos across Europe.

Hours after the accident toxic black smoke was still billowing from the tunnel's vents, prompting the authorities to advise residents of nearby villages to close their doors and windows and remain inside.