Victims of the contaminated blood scandal have won the right to sue the government in the High Court in a new legal case over the health disaster.

More than 500 people who were either infected with HIV or hepatitis C from blood products or are families of the dead are taking the landmark action - including two St Neots families whose lives were torn apart.

In a hearing at the Royal Courts of Justice lawyers acting for the Department of Health tried unsuccessfully to delay the court case, arguing it was “premature”.

But the bid was blocked by a judge who said it was “appropriate” for the group legal action to go ahead.

It means victims of one of the worst disasters in the history of the NHS can now try to force the government to accept liability for the scandal and win compensation through the courts.

Jason Evans, founder of Factor 8 Campaign UK, whose father died of HIV and who is the leading the group litigation, said: “It’s incredible. I don’t think the smile is going to leave my face for a while. It was the absolute best outcome we could hope for.”

The case concerns the use of blood-clotting products in the 1970s and 1980s made from plasma donated through high-risk sources, such as prisoners and paid donors in the United States.

These factor products caused people with the blood disorder haemophilia to be infected with HIV and hep C, and an estimated 2,400 people have so far died.

Among those involved in the law suit are Tony Farrugia, and Christopher Smith, of St Neots, whose fathers both died from Aids contracted from blood factor products.

Mr Farrugia, 45, who was placed into care when his dad died, aged 37, said: “Finally we might be on the road to justice. It has been a long time coming. For us personally it’s about liability and having dad’s death recorded correctly in history.”

Mr Smith, 39, a senior manager at LG Electronics, said his father’s death aged just 32 had “killed the family business and killed some of the family in the process as well”.

“We lost everything,” he said. “I can still remember being eight-years-old in bed looking up at the ceiling and asking ‘Why, what have I done so wrong?’ I have to actually make dad’s death mean something.”

The court hearing on September 26 follows an announcement by the prime minister in July that a public inquiry is to be held into the blood disaster.