A Labour MP has asked Whitehall's top civil servant to investigate whether Theresa May's advisers broke the rules by planting negative stories in newspapers about the former UK Border Agency chief, Brodie Clark.
Simon Danczuk wrote to Sir Gus O'Donnell on Thursday asking him to investigate who was responsible for passing to the media allegations about Clark, which were reported over the weekend and attributed to "Home Office sources" and "senior sources".
He writes: "I am writing to raise serious concerns about suggestions that advisers to the home secretary may have been briefing against a serving civil servant who had been suspended and therefore had no right to reply.
"A number of allegations about Brodie Clark, who had just been suspended as the head of the UK border force, appeared in newspapers over the weekend.
"These included allegations about what Mr Clark authorised, and claims that 'officials have been instructed to refuse any offer of resignation make by Mr Clark, which would trigger discretionary payment to him'.
He adds: "This claim, if true, must have come from inside the Home Office."
Danczuk quotes extracts from a Daily Mail article that suggested criminal charges could be brought "against anyone found to have put Britain's borders at risk."
He also refers to a story in the Daily Telegraph said Home Office sources described Clark as a "rogue civil servant" who could be sacked by the end of the week.
Danczuk claims that if the information about Clark came from one of May's advisers it would be a breach of the code of conduct for special advisers.
The code states that the "preparation or dissemination of personal attacks have no part to play in the job of being a special adviser".
"All contact with the news media should be authorised by the appointing minister," it adds."Special advisers must not behave towards permanent civil servants in a way which would be inconsistent with the standards set".
The Home Secretary and Clark have been engaged in a war of words over the last few days over which one of them was responsible for relaxing border controls at Britain's airports that let an unknown number of people into the country.
Clark is suing the government for constructive dismissal.