A failed Brazilian asylum seeker has been found guilty of leaving a fake stick of dynamite outside MI5 headquarters, just one day after being notified that he would be deported from the UK.
Brazilian national Julian Valente Pereira, 32, mocked up an explosive device with rolled-up A4 paper, brown masking tape, and string to mimic a fuse, and left it outside Thames House in central London.
The incident happened on January 1, the day after Pereira's final appeal for asylum had been dismissed by a judge.
An explosives expert from counter-terrorism policing had to be drafted in after MI5 CCTV operators spotted Pereira dropping the device near the front doors of the building along with a green cigarette lighter, City of London Magistrates' Court heard.
Pereira, who admits he 'hates the Home Office' and says he has been 'tortured' during five years in the asylum system, denied carrying out a bomb hoax - insisting he never intended for anyone to believe the device was real.
But Chief Magistrate Paul Goldspring found him guilty, concluding Pereira knew he was being watched - blowing a kiss to the CCTV operator - and intended to cause fear of an explosion.
Branding Pereira 'manipulative' during his evidence, the judge said: 'You had without doubt foresaw that someone would believe it was a genuine device until closer inspection, capable of being ignited by a lighter, and if it was they would believe it would explode.'
Pereira has been remanded in custody until sentencing on April 1.
Pereira told the court he had also visited Buckingham Palace to throw a bag containing a copy of the immigration ruling and a knife stabbed through his ID inside the perimeter gates.
Prosecutor Shannon Revel told the court Perreira has admitted he wanted 'maximum attention' on his complaints against the Home Office.
'No-one was going to pay attention to this act if they thought it was masking tape and paper,' she said.
'The attention he desperately wanted on January 1 is only achieved by the fact that someone believed that object could explode.'
The court heard that Pereira, wearing a hoodie adorned with a St George's Cross, which the judge branded 'inappropriate', came to the UK with permission to work in July 2018 and has remained in the country illegally since February 2019.
'The defendant attended Thames House in Millbank, knowing it to be the headquarters of the security services MI5,' said Ms Revel.
'He tried to open the doors of the building without success.
'He started to push pieces of paper between the closed doors that were locked.
'He took an item fashioned from paper, string and masking tape out of his jacket pocket.
'The object was designed to look like a stick of dynamite.'
The court was played CCTV of Pereira throwing the object to the ground, then placing it up against the doors of the MI5 headquarters with the lighter.
'At the time, it wasn't possible to tell whether the dynamite stick with a fuse was real or not,' said Ms Revel.
The Crowne Plaza hotel in West Drayton is thought to be one of the UK's longest opening asylum hostels. Pereira was arrested in his room at an asylum hotel in Uxbridge, west London.
She said the counter-terrorism explosives expert later declared the incident as a hoax.
Giving evidence, Pereira said he left the object at the front of MI5 because he wanted to 'catch the attention' of the security services.
'I swear it wasn't my intention to cause any disruption on Vauxhall Bridge,' he said.
He told the court he had also visited Buckingham Palace to throw a bag containing a copy of the immigration ruling and a knife stabbed through his ID inside the perimeter gates.
In messages read out during the trial, Pereira had told a friend of his plan.
'I'm going to Buckingham Palace with a knife and one pen drive,' he wrote, adding: 'All the information is inside the pen drive.'
When he was told to 'stop being an idiot', Pereira wrote: 'I'm going to try and get attention.'
'I'm going to throw the bag into Buckingham Palace.'
In a note on his phone from August 2025, Pereira wrote about 'MI5 terrorising people inside hotels', and added: 'I need to see the King.'
He also said he planned to 'give information' to the Archbishop of Canterbury as a precaution.
When giving evidence, Pereira insisted the device he left outside MI5 would not have been mistaken for an explosive, but added: 'The news inside was dynamite.'
Pereira was arrested in his room at an asylum hotel in Uxbridge, west London, and told officers about his 'long and tireless battle with the Home Office to try to attain asylum', said the prosecutor.
The court heard that Pereira made allegations of Home Office 'corruption', claimed illegal immigrants are employed by the Government department, and said those in the system are living in 'squalor'.
Judge Goldspring was also told that Pereira handed himself in to police as an overstayer in October 2020, but later sought asylum after being told to leave the UK.
He was placed in asylum-seeker accommodation in June 2021; asylum was refused in 2023; and his appeal against that decision was rejected by a judge on December 31 2025.
The court heard that Pereira's paid-for accommodation was withdrawn on January 9.
In his police interview, he told officers he has schizophrenia and had been hearing voices in his head.
He denied carrying out a bomb hoax by placing an article with intent.
The judge asked for reports on Pereira's mental health and risk of reoffending, and warned that he may be jailed or sent to the Crown Court for sentencing.