Paul Nuttall’s press officer has offered to resign after saying she was to blame for “mistakes” in statements about the UKIP leader’s involvement in the Hillsborough disaster.
Mr Nuttall earlier admitted claims on his website that he had lost close friends in the 1989 tragedy were false.
Lynda Roughley said she was “entirely responsible” for two press releases that were posted in 2011 and 2012.
Hillsborough campaigners have accused Mr Nuttall of “insensitivity”.
Ms Roughley’s comments follow a day of confusion in which Mr Nuttall, who is contesting the Stoke Central by-election, was forced to issue a statement clarifying his position and emphasise once again that he had witnessed the tragedy in person with his family.
While he said he knew people who had died in the disaster, the MEP for the North West of England said he was “appalled” the impression had been given by the statements that he was personally close to any of the 96 victims.
He said he did not check press releases posted by an aide on the subject suggesting as much and was “very sorry” for the oversight.
In her statement, Ms Roughley said she was “mortified” at the distress caused.
“I am entirely responsible for the website post regarding Paul’s comments about having ‘close friends’ who died at Hillsborough,” she said.
“Paul is a man of great integrity and would not say something he knew to be untrue. It’s me who has made this mistake, and one I feel absolutely terrible about.”
The Sun reported that Ms Roughley’s resignation had been turned down.
Mr Nuttall was pressed about the website posts during an interview with Liverpool’s Radio City station on Tuesday.
He later responded to questions about whether he was, as he has long insisted, at the match itself by speaking in more detail of the effect the occasion had on him.
“As a 12-year-old boy, I travelled to Sheffield that day, as did so many others, to enjoy watching the team that I loved,” he said.
“From the upper tier of the Leppings Lane End, I watched the events of that day unfold with horror… Like everybody connected to the Hillsborough disaster, memories of 15 April 1989 bring me nothing but pain and upset.”
But Hillsborough Family Support Group chairwoman Margaret Aspinall told LBC the website errors were “an insult” to people who did lose somebody on that day.
And Barry Downside – whose son Christopher died in the tragedy – said the UKIP leader should have “known better”.
“It’s insensitive. We are still awaiting the decision of the Crown Prosecution Service as to whether charges will be brought and we don’t need this kind of thing.”