A Chesterfield terror suspect allegedly used his former chip shop as a 'laboratory' for carrying out different types of explosions, a court heard.
Andy Star, 32, the former owner of Mermaid Fish Bar, on Sheffield Road, Chesterfield, is on trial at Sheffield Crown Court for allegedly plotting a terror attack in the UK in support of Islamic State - a charge he denies and claims is down to an innocent interest in homemade fireworks.
His co-defendant, Farhad Salah, 23, of Brunswick Road, Sheffield - who also denies the same charge - is alleged to have been looking into an attack involving a driverless car bomb controlled by a laptop to spare themselves.
No information has been heard about the identity of the location of the alleged attack.
On the second day of the trial, Anne Whyte QC, prosecuting, said: "In that plan, Andy Star was a willing and technical helpmate."
The pair were arrested at their separate addresses on December 19 last year.
The prosecution allege that both men were working together in planning an attack.
But the 'principle testing ground' was at Mr Star's then premises, the Mermaid Fish Bar.
"There he (Star) stockpiled substances and components that could be used to experiment and test on small but significant different types of explosives," Ms Whyte told the court.
"He tried to do some of this in plain sight by affecting that any substances were simply to do with an innocent interest in fireworks."
The court heard how Mr Star allegedly sent Salah a video on how to make gunpowder called 'How to make black powder - easy'. An expert concluded the method on the video was viable.
On December 13 last year, Mr Star apparently created three videos on his phone - one of which showed a 'white coloured lump' resembling cotton wool being ignited by a cigarette. The video was filmed in a small bedroom at the Mermaid Fish Bar, it is claimed.
In terms of Mr Salah, a similar type of homemade video was allegedly found on his phone, taken at the Fatima Community Centre in Sheffield.
On December 14, 2017, Mr Salah apparently sent a message to a contact saying: "We have made invention in the field of explosion. We have produced a substance. If you put it in any explosive it triples power... and also controlling vehicle with laptop and without driver."
A further message alleged to have been sent by Mr Salah to a contact talking more about the use of a vehicle controlled by a laptop, said: "None of our brothers need to get inside it. It is safe for them, all of it is laptop with camera, will be controlled to the place you want to take you can."
On this, Ms Whyte said: "The prosecution say this is the clearest evidence that Salah and Star together had been testing from a very low level how to make and ignite explosives."
More evidence was heard that alleges Mr Salah had still not given up on the idea of travelling to Syria to fight for IS.
Further prosecution evidence alleged there was a level of trust between both men as they allegedly promised to delete video footage of test explosions.
Mr Salah apparently told police his Facebook account had been hacked - something the prosecution allege is a 'smokescreen'. He denies any involvement in terrorism.
Mr Star denies any involvement in terrorrism and supporting IS. He agreed that he made homemade fireworks and left some of the remains in the loft for Bonfire Night. He added any sulphuric acid in his premises was used to clean draines.
Ms Whyte added: "We allege that both men were working to a common purpose in their own way but together."
The trial, expected to last up to four weeks, continues on Monday.