Labour politicians on Bradford Council were last night condemned for covering up the real reason why disgraced Methodist minister and former Co-operative Bank chairman Paul Flowers had quit as a councillor.

The Council was forced to reveal yesterday that Mr Flowers “resigned immediately” after pornographic material was found on his work laptop by its IT staff in September 2011.

At the time, his resignation was attributed by the Labour group – which still runs the authority – to time pressures, as he juggled his Council work with his financial role as chairman of the Co-operative Bank.

The shock revelation has led to the Council’s Tory opposition leader Councillor Glen Miller saying he will be raising his concerns with the Council’s chief executive Tony Reeves.

When he stood down, Mr Flowers, 63, who is now embroiled in an illegal drugs and gay sex scandal, said he was unable to carry out both jobs.

He said: “It has become clear to me that, over the longer term, I will be unable to sustain the workload associated with performing both roles to the best of my ability.”

The leader of the Labour Group at the time, Ian Greenwood, said: “I will be sad to see him go but I fully understand the reasoning behind Paul’s decision.”

The statement released by the Council yesterday told a very different story.

It said: “Inappropriate but not illegal adult content was found on a Council computer handed in by Councillor Flowers for servicing. This was put to him and he resigned immediately.”

Coun Miller said the revelation was “an extreme shock”.

He said: “I wish the Rev Flowers well with his recuperation but I will be asking questions at my next one-to-one with the chief executive about why this was never mentioned or no information given.”

Councillor Jeanette Sunderland, the Council’s Liberal Democrat leader, said her group had not been told until now why Mr Flowers had resigned.

Councillor Geoff Reid (Lib Dem, Eccleshill), a retired Methodist minister, said: “Some people at the top of the Council knew about it, but we didn’t. There are questions that need to be answered, but I’ll leave that to others.”

Mr Flowers, who lives in Great Horton, had been a Bradford councillor for ten years when he resigned.

Former Council leader Mr Greenwood, who is no longer a councillor, was unavailable for comment yesterday.

Neither the Labour group’s current leader, Councillor David Green, who is now leader of the Council, nor its chief whip, Councillor Sher Khan, would comment on yesterday’s revelations.

The Labour Party office for Yorkshire and the Humber refused to say whether the real reason for Mr Flowers’ resignation as a councillor had been passed on to the Co-operative Group at the time.

A Labour North spokesman would only say: “Paul Flowers has been suspended as a member of the Labour Party for bringing the party into disrepute.”

Mr Flowers, who resigned as the Co-op Bank’s chairman in May, is now the subject of a police investigation into reports that he bought and used illegal drugs, including cocaine, crystal meth and ketamine. Mr Flowers has apologised over the scandal and has been suspended by the Methodist Church as well as the Labour Party.

The Co-op is now trying to plug a £1.5 billion gap in finances which was discovered following the purchase of the Britannia Building Society in 2009 and abortive plans to buy hundreds of Lloyds branches.

The Methodist Church last night confirmed it had not been aware of the circumstances of Mr Flowers’ departure from Bradford Council. A spokesman said: “We were not privy to that information until this afternoon.”

When the Telegraph & Argus asked the Co-operative Group whether it knew why Mr Flowers had been forced to resign as a councillor, a spokesman said: “We cannot comment on specific allegations. Our investigation will look at any issues and misgivings, and will include all information that is brought to our attention.”

e-mail: claire.armstrong@telegraphandargus.co.uk