Blacklisting campaigners shut down a Salford power station construction site yesterday, alleging that bosses had refused to employ a local trade union activist.

Carrington gas-fired power station is under construction on the site of a former coal-fired power station in Greater Manchester with contractors DF Energy and Allston.

Campaigners said that bosses at the site were operating a blacklist and that they refused to employ a local man who works as a scaffolder and activist with union Unite.

Around 50 campaigners blockaded the site yesterday morning saying that workers had been turned away and that work at the site was halted.

"This was a protest against blacklisting. A scaffolder who is a local man has been blacklisted. We blocked the road and stopped production at the site. We are demanding he is given a job on the site," said former Agecroft miner Paul Kelly.

Among the protesters was highly respected activist George Tapp, a construction electrician who was a victim of blacklisting for many years.

Mr Tapp suffered severe leg injuries two years ago when he was mown down by a driver during a protest at a Manchester construction site.

The scandal of blacklisting in the construction industry was revealed when a raid by government officials on the Consulting Association in 2009 uncovered a list of more than 3,200 construction workers who were union activists or had raised health and safety issues.

Unions including Unite and the GMB are pursuing legal action against a number of construction firms to win compensation for victims of blacklisting.

Some victims are still unaware that they were on the list.

The three-year Carrington power station project is due for completion in 2016 and will generate enough electricity to supply around a million homes.

The campaigners were set to meet outside the site today at 8am to plan their next moves.