The disgraced spin doctor Jo Moore has been accused of bullying by the civil servant's union.

At a Commons committee meeting on Thursday, Stephen Byers' former press advisor was alleged to have dealt with civil servants in a manner which was "an almost textbook case of bullying".

Jonathan Baume, general secretary of the Association of First Division Civil Servants, told MPs that Moore, who infamously described September 11 as a "good day to bury bad news", ignored civil service impartiality rules.

He was giving evidence to the influential Commons Public Administration Committee's inquiry into the relationship between civil servants and special advisers.

"My perception is that Jo Moore was forceful and aggressive to the point that she bullied and victimised civil servants both in the press and related policy areas. Her behaviour was described to me as an almost textbook case of bullying," said Baume.

"She appeared...to have no grasp of the concept of the political impartiality of the civil service, or if she did she ignored it. It was completely unacceptable."The committee also heard from the government information service's chief, Mike Granatt, who claimed the resignation of Martin Sixsmith - which had caused the latest spin row - was purely a matter for the department concerned and not part of a wider problem.

"If it was necessary to look across the whole system because I felt it was a widespread, endemic problem, then clearly that is something on which I would take a view. I think it is reasonable to point out that what we are seeing at DTLR is not happening across the rest of service," he said.

The Opposition said the revelations simply reaffirmed the fact that Moore should have resigned earlier and showed how Byers had allowed his department to fall apart.

Shadow cabinet office minister Tim Collins described the evidence to the committee as "devastating".

"Stephen Byers was wholly wrong to appoint Jo Moore in the first place and wholly wrong to keep her. It turns out that her misbehaviour was as big a problem at the DTI as at the DTLR. The descriptions of her conduct revealed today make it utterly unacceptable for there to be any question of her receiving a pay-off from the taxpayer as a result of her departure," he said.

"The government's much promised and constantly delayed Civil Service Bill must be brought forward immediately if civil servants are to be given the statutory protection they now desperately need from the ever more thuggish tactics of new Labour."