Reform UK deputy leader Richard Tice blasted the police after revealing new details from an incident last Christmas

Reform UK leader Nigel Farage has been left "horrified" after counter-terror police last night reopened an investigation into an alleged firebombing at his home.

Mr Farage, who is campaigning ahead of the Clacton by-election, revealed earlier this year that a “lit incendiary device” was pushed through his letterbox.

Police investigating at the time believed the incident was an attempted burglary gone wrong.

However, counter-terror officers admitted there was a line of inquiry “which was not identified and pursued by them at the time, which may have been relevant”.

Counter Terrorism Policing London also made a mandatory conduct referral to the Independent Office for Police Conduct following the blunder.

The IOPC confirmed the referral centred around the conduct of one staff member who is accused of failing to identify and pursue a line of enquiry.

A Reform UK source told The Sun on Sunday: “There has been a very serious policing error which is why [CTP] have referred themselves to IOPC, which is unprecedented.”

Police continue to investigate potential terror offences after Ann Widdecombe, 78, was bludgeoned to death at her Devon home last month.

There is no suggestion from police that the two events are linked.

Meanwhile, Reform UK's deputy leader Richard Tice also accused the police of failing to take threats to figures associated with the party seriously.

He said: “Only recently have the authorities woken up to the abuse and intimidation I and other Reform MPs have had, despite plenty of real examples that we have provided.

“For too long, the threats we have faced have not been taken seriously.

“The fact that the police have referred themselves to the IOPC speaks for itself. They recognise that they’ve messed up.”

Mr Farage, who was the victim of two assaults ahead of the 2024 General Election, said he received 1,500 threats between February and July.

There were almost 600 death threats directed towards the Reform UK leader, with one social media user being arrested on July 15 on suspicion of sending threatening communications.

Scotland Yard's Assistant Commissioner Laurence Taylor, who heads up Counter Terror Policing, also admitted investigating whether Ms Widdecombe's murder suspect was targeting "other Reform politicians".

Joshua Kerr, 28, from Rotherham in South Yorkshire, is believed to have been in Ms Widdecombe's home for just two minutes on July 8.

He is accused of driving for more than 250 miles to her Devon home before returning to South Yorkshire.

The 28-year-old appeared in court last month charged with murder and remains under arrest on suspicion of the commission, preparation or instigation of acts of terrorism.

He has not entered a plea and remains in custody ahead of a trial scheduled for next June.

Mr Tice today revealed that he had to use his own panic button following an interaction just before Christmas.

The Boston & Skegness MP told The Telegraph that police officers made an arrest following the incident.

Following Ms Widdecombe's death, Reform UK provided its MPs with round-the-clock security amid a row with the authorities over cuts to taxpayer-funded protection for Mr Farage.