Safety checks were carried out on railway tracks across Britain on yesterday after a high speed train crash in northern England killed an elderly woman and seriously injured several other passengers.

A Virgin Pendolino tilting train, heading from London to Glasgow, derailed at 150 kph on Friday evening in a remote area of Cumbria, scattering carriages down the side of a steep embankment. Accident investigators said their inquiry was concentrating on a set of points.

?Clearly that?s the focus of attention and has been for the last 24 hours,? John Armitt, Network Rail chief executive, told Sky News.

Track operator Network Rail said it had started safety checks on about 700 sets of points across the country but so far nothing out of the ordinary had been found.

Armitt said he could not confirm reports sabotage was a possible cause of the accident or that there were bolts missing from the rail. The set of points in question had been inspected on February 3, he said.

A preliminary report by accident investigators was expected on Monday, he added.

Driver praised

Richard Branson, chairman of Virgin Group, praised the train?s driver who remained in his seat after the train derailed in an attempt to slow it down. Some of the 100 passengers were trapped in the overturned carriages.

Police named the dead woman as 84-year-old Margaret Masson, from Glasgow. Eleven people are still in hospital with back, leg and head injuries and officers said it was ?little short of a miracle? more passengers had not died.

?We are amazed that we didn?t have fatalities actually at the time. We?ve been very, very fortunate,? said Chief Superintendent Martyn Ripley of British Transport Police. In 2002, seven passengers died in a derailment at Potters Bar, north of London. Two years earlier four people were killed in a derailment at Hatfield near London.

The worst accident in recent years happened in 1999 when two trains collided near the capital?s Paddington station, killing 31.

Bob Crowe, general secretary of the Rail Maritime and Transport union, said the latest accident demonstrated that lessons had not been learnt from previous accidents.

Missing bolts were blamed for the failure of the points system which led to the Potters Bar crash.

?It?s all pointing to the way something?s seriously gone wrong with the points,? Crow told Sky News.

Rail experts said safety features of the Pendolinos had restricted casualties. The Pendolino (Italian for ?tilting?) was developed in Italy by Fiat Ferroviaria, which was bought by French firm Alstom in 2000.

Virgin Trains is 49 percent-owned by British bus and train operator Stagecoach Group Plc and 51 percent by Virgin Group.