Yvette Cooper would have been informed of Southport attacker’s terror guide ‘within hours’

A No 10 spokesman said it was “untrue” to say the Government was hiding the facts and that it was the responsibility of the police and the Crown Prosecution Service (CPS) to “speak on behalf of investigations and charging decisions”.

Sir Keir Starmer accused the two Conservative leadership candidates of “undermining the police” in their tough job with their comments.

The former senior counter-terrorism official said the Home Secretary would be informed of the alleged discovery of ricin and terrorism-related material once police discovered it. Not doing so would have been a “serious mistake” under normal protocols, they said.

“He immediately comes out on top, and he should. I can’t understand why it wasn’t forwarded to the Ministry of Internal Affairs the day they found it. That’s definitely what was going to happen. “It is impossible to find ricin in the presence of a suspect whose triple murder you are currently investigating and not tell the Ministry of Internal Affairs,” they added.

They said this would be passed on to counter-terrorism police in the north-west, who would inform Matt Jukes, head of UK counter-terrorism policing, who would then report it to the Home Office.

Unless it was determined that there was a serious threat to public safety, such information did not necessarily have to be passed on to the Prime Minister; but the former officer said that in such a high-profile case it was probably No. He believed it would be told to 10.

But they said it was right for politicians not to disclose such information. “This is a live police investigation. Charges have been made, but there may be other charges as well. “It is not the job of politicians to interfere with justice,” said the former police officer.

“This is the job of the Attorney General, the Attorney General’s Office. Justice is on its way. “There is no interference from politicians.”