A legal battle for more than £4 million compensation has begun over the Hatfield rail crash, which killed four people including Sussex man Stephen Arthur.

Solicitors acting for the families of each of the four victims issued a claim form in the High Court in London against Railtrack, which has already admitted liability for the accident.

Mr Arthur, 46, of Old Brighton Road, Pease Pottage, near Crawley, was killed when a GNER London-Leeds express train was derailed in Hertfordshire in October 2000. The crash was caused by a broken rail.

The father of two ran an aviation business and was on his way to Leeds to fly passengers to Jersey in a private jet.

The others who died were airline pilot Robert Alcorn, 37, of New Zealand; advertising executive Peter Monkhouse, 50, of Leeds; and solicitor Leslie Gray, 43, of Nottingham.

John Pickering, head of personal injury at law firm Irwin Mitchell, which represents the families, said: "Railtrack has made interim payments but there has been no agreement on final sums.

"We are fighting to get compensation in seven figures for each family."

Papers will now be served on Railtrack but it may be some months before the case is heard.

Mr Arthur's widow, Lesley, 35, said today: "I've had one interim payment which you get if you need help financially. It has been hard because it's a long time without any income coming in."

Mrs Arthur said she had spoken to her lawyer last week about the compensation claim but was waiting to hear more news.