A CHEMISTRY student whose home made bomb blew the door off his parents' garage has been jailed for 14 months.

Edward Mattison, 21, who was obsessed with bombs, made "suicide bomb" explosives known as Mother of Satan in his family home after research on the internet.

Minshull Street Crown Court, Manchester yesterday heard how the "thrill seeking" young man had been responsible for several explosions, including one which killed a sheep in a field.

He was finally caught when one of his bombs blew the door off the garage of his parents' £450,000 house in Brereton Drive, Worsley.

Bomb squad officers later found he had been storing dangerous chemicals used to make explosives, including the powerful substance triacetone triperoxide, or TATP - the chemical, known as "Mother of Satan" because of its unstable nature which was used in the July 7 bombings in London.

Mattison was sentenced to 14 months in prison after admitting possession, creating and using explosives.

He was also given a two-year Anti-Social Behaviour Order, banning him from making or researching explosives, and operating websites or publishing material relating to the use or making of explosive substances.

In court, a video made by Mattison was played showing him lighting a device in a field near the M60 in Worsley which caused an 8ft wide crater and showed a 40-metre area with metal fragments.

Gary Woodhall, prosecuting, said the explosion caused a large mushroom of thick dense smoke and one witness driving along the motorway described feeling a shock wave.

In a second incident, Mattison was found to have exploded a device in his parents' garage.

A neighbour had first become concerned when hearing a blast coming from the garage in the summer of 2004 which was so loud it made his house vibrate..

He heard another explosion coming from the defendant's home at 6pm on May 20 last year and saw smoke "He and his friend went to the garage to investigate," said Mr Woodhall.

"They saw a wooden door lying on the floor, smoking, and the defendant standing inside with a digital camera on a tripod."

Mattison claimed the explosion was caused by a large firework and told them to leave.

But the neighbour's friend, an off-duty policeman, produced his warrant card, and called police.

Mattison tried to run off, but was held by the men until police arrived and arrested him.

Bomb squad officers were called in to search the house after police found what they thought were pipe bombs and further searches of Mattison's bedroom uncovered homemade gunpowder and material found in pyrotechnic powder.

Mr Woodhall said: "They were capable of causing injury, possibly serious, to people and property within the vicinity."

They also found magnesium and potassium nitrate and TATP, a powerful and unstable explosive.

Mr Woodhall said: "In the quantity recovered, had it ignited, it would have at least caused substantial damage to the bedroom, and would have killed or very seriously injured anyone close to it if mishandled."

The substance was destroyed in a controlled explosion at the house.

Searches of the computer in Mattison's bedroom showed he had been looking at explosives websites. He had contributed to on-line discussions and boasted about putting 20g of explosives in a tree trunk and blowing up a 12kg metal beer keg in a wood.

Officers searching a computer recovered from his home also discovered he had downloaded pornographic pictures and videos of children from the internet.

Mattison was given a two-year conditional discharge after admitting possessing indecent images of children, although he claimed he had downloaded them accidentally.

Mr Woodhall said Mattison admitted to police that he had a keen interest in chemistry and that he had carried out explosions when no one was around or in danger.

He said: "He admitted what he was doing was not safe, and that it was dangerous beyond his understanding.

"He said he was thrill seeking."

Jamie Hamilton, defending, said the explosives had not been passed to anyone else by Mattison. He said: "His purpose was experimentation, thrill seeking and putting together from a chemical point of view these devices."

Sentencing Mattison, Judge Adrian Lyon said: "That a young man should experiment, should operate websites, should gather together materials from the internet,shows a determination, organisation, ability and intention to carry out that which you knew to be illegal and, furthermore, dangerous."