A man suspected of carrying out a petrol bomb attack at a migrant processing centre in Dover appears to have posted anti-Muslim rants on social media.
Two staff members from the centre sustained minor injuries. Leak killed himself in his vehicle in the car park of a nearby garage later that day.
The investigation into the firebombing attack is being led by counter-terrorism police, and officers believe it was fuelled by "some form of hate-filled grievance".
A search has been carried out at a property in the High Wycombe area and "a number of items of interest were recovered, including digital media devices", Thames Valley Police said.
It added there was "currently nothing to suggest the man involved was working alongside anyone else".
Social media posts shared on Andrew Leak's Facebook page contain anti-Muslim sentiments and complaints about people claiming benefits if they do not speak English.
Leak also shared an anti-royal family post, saying: "Prince Charles says he's going to house Ukrainian refugees in one of his properties that belong to the British people, what about soldiers and members of the public sleeping in doorways? Disgrace. End the royal family now."
One of Leak's neighbours, Allan Abbott, 61, told Sky News: "Andy would bend over backwards for anyone. I was shocked. He was always cheerful, always singing. He had rheumatoid arthritis and cancer."
Leak's benefits were 'cut in half'
Mr Abbott recalled how he and Leak were sitting in a garden during the summer and Leak was "so upset" after a migrant boat sank.
Mr Abbott said Leak questioned "why doesn't the British government help them", adding his neighbour was "distressed about the whole thing".
He went on to say that Leak told him a few months ago that his benefits had been "cut in half" and he had to sell some of his clothes.
Meanwhile, a woman who lives near Leak's former address said she had occasionally seen him in a wheelchair in the local area and thought he might have mental health problems.
Asked what her impression of him had been, the carer, who is in her 40s and did not wish to be named, said: "One minute he was in a wheelchair, the other he was walking."
Leak has been described by North Thanet MP Sir Roger Gale as having "severe mental health difficulties".
Following Sunday's attack, the Explosive Ordnance Disposal Unit was called to ensure there were no further threats.
The centre is where people arriving into Dover via small boats are taken for the first stage of their asylum processing.
A total of 700 people were moved to the Manston centre in Kent, around 20 miles away, for safety reasons.