Comedian Mark Thomas has spoken of his anger after discovering his name on a blacklist drawn up for construction companies.

He said he was “shocked” to find that he had been included on secret files of thousands of mainly building workers. Most do not know they were on the list.

Thomas’s name was found by the GMB union, which is pursuing compensation on behalf of a number of its members and others such as environmental activists.

The comedian said: “I wasn’t massively surprised, but I was shocked. I don’t work in the construction industry, although I have been involved in campaigns against the activities of building firms.

“But to include a comic in all of this is just nuts.”

Thomas said he suspected the police colluded with construction firms to collect information.

He said: “This needs to be highlighted and the police should be held to account. There has to be a proper investigation, such as a parliamentary inquiry to make sure this kind of behaviour is outlawed.”

His case is now being taken up by the GMB. Last week major construction firms announced plans to compensate workers on the blacklist.

The development followed years of campaigning by unions after it was discovered that more than 3,200 names of workers were kept on a file drawn up by the Consulting Association.

Workers involved said they were denied work for years, often merely for raising legitimate concerns about health and safety on building sites.