FAMILIES of four men who were thrown 80ft to their deaths from a motorway bridge called for tough laws to deal with companies last night after an inquest jury decided the men were unlawfully killed.

Two North-East men were among the workers who plunged from the M5 Avonmouth bridge, near Bristol, when the brakes on their gantry failed to stop it being blown by the wind along beams under the bridge.

One end of the gantry became detached from the beams, throwing the workers to the ground.

Paul Stewart, 23, from Newcastle, Andrew Rodgers, 40, from Middlesbrough, Ronald Hill, 38, from Glasgow, and Jeffrey Williams, 42, from Newport, died of multiple injuries.

They had been employed by Darlington firm Kvaerner Cleveland Bridge UK Limited, now known as Yarm Road Limited, and Costain, to carry out the strengthening work.

After the verdict at the Bristol inquest yesterday, the families of the victims and the GMB union united in calls for companies to face tougher measures in cases of corporate killing.

Mr Stewart's father, George, said: "It's taken a long hard fight. I was not looking for vengeance - I'm looking for justice not only for my son but for the other three men that died."

Solicitor Brian Freeman, speaking on behalf of the families, said the inquest had been the only time bosses had given a detailed account publicly for their "actions or inactions".

He criticised the companies' risk assessment reviews, monitoring of gantry movements and wind, training and reaction to a previous incident involving a gantry.

He said: "Strong laws to deal with corporate killing must be created so that no other families have to suffer the way these families have.

"Only strong laws against corporate killing can ensure that the minds of those running companies are sufficiently focused to avoid innocent men and women dying at work."

The GMB union had funded the legal representation for the families at the inquest.

Kevin Curran, union general secretary, said: "The GMB welcomes this verdict .

"But we are also angry that the current state of the corporate killing law has hampered our members' families fight for justice right from the start.

"I urge the Government to look at this case and get tough with negligent employers."

A spokeswoman for the Health and Safety Executive said it would be liaising with police over the role of individuals working at the time of the accident for the companies involved.

Costain and Kvaerner Cleveland Bridge were prosecuted under the Health and Safety Act following the deaths in September 1999 and were fined a total of £500,000 after pleading guilty.

The relatives of the men were awarded £1.3m compensation.

At the end of the inquest, deputy coroner for Avon Brian Whitehouse said: "I hope this inquest has gone some way at least towards exposing all the facts.

"The men deserve that and so do their families and I hope that the construction industry has fully taken on board the lessons learned from this case."

A spokesman for Costain said the company wished to express its condolences to the families of the deceased but had no further comment to make.