The firebombing of an immigration processing centre in Dover by a High Wycombe man was motivated by an extreme rightwing terrorist ideology, police have said.

Andrew Leak, 66, who lived in Wooburn Green, is believed to have killed himself after throwing two or three "crude" incendiary devices at the Western Jet Foil site, in Kent, last Sunday.

The counter terror police have spoken to a number of "significant witnesses" and a number of items of interest have been recovered.

Evidence from examining the digital media devices recovered during the investigation is said to suggest “an extreme right wing motivation behind the attack,” police said.

Two people suffered minor injuries and the suspect was later found dead at a nearby petrol station, the force added.

Tim Jacques, Senior National Coordinator for Counter Terrorism Policing, said: “This was clearly a very worrying incident and although nobody was seriously hurt, two people did sustain minor injuries.

“Increasingly in counter terrorism casework, across all ideologies, we are seeing individuals who have mental health concerns and a hateful mind-set.

“Assessing when this crosses the terrorism threshold is a complex process and needs to be carefully considered on a case-by-case basis.

"These decisions need to be determined by the facts, as far as they can be established at any given time.

“After considering the evidence collected so far in this case, whilst there are strong indications that mental health was likely a factor, I am satisfied that the suspect’s actions were primarily driven by an extremist ideology.

"This meets the threshold for a terrorist incident.”

Police said there is no evidence to suggest Leak was working with anyone else or that there is any wider threat to the public.

Facebook posts on a now-deleted account under the name of an Andy Leak from High Wycombe contain anti-Muslim sentiments and complaints about people claiming benefits if they do not speak English.

One, shared on August 9, said: “The next time the job centre sanctions your money for not looking for enough work ask them about the thousands of people getting benefits cannot speak English and can not write English, how are they looking for work?

“Unemployment benefits clearly state you cannot claim benefits if not looking for work, all of these people should be excluded from benefits.

“You can clearly not look for work if you cannot read English or speak English, they are breaking the law, time to stand up.”

Another post, on July 24, said: “All Muslims are guilty of grooming, they never spoke out because it wasn’t their daughters, f****** animals wake up up.

“They only rape non-Muslims that’s a religious hate crime are you f****** stupid.”

Two members of staff at the centre were left with minor injuries after police were called at 11.22am on Sunday morning.

Following the incident, 700 people were moved to Manston asylum processing centre near Ramsgate for safety reasons.

Police said the investigation is ongoing, including work being carried out on behalf of His Majesty’s Coroner.

An inquest into Leak’s death is expected to be opened at Maidstone’s County Hall on Tuesday.