Neil Hooson claimed he viewed the images purely for "research purposes", but a judge at Preston Crown Court told him he had to go to prison as the children depicted being sexually abused were so young.

Hooson, 35, of Watering Pool Lane, Lostock Hall, pleaded guilty to 22 offences of possessing obscene photographs of children - some 292 images, of which 13 were 'level five', the most serious.

Joanne Shepherd, prosecuting, said police investigating paedophilia chatrooms seized Hooson's computer from his then-home in Walton Avenue, Penwortham. On it they found images he had viewed and tried to delete of babies being abused.

The court heard Hooson had been a scout leader in Bamber Bridge, and an IT technician with the county council for five years, and defence counsel Mr Christopher Hudson called him to the witness box to give evidence.

Hooson told the court that, after an incident when he was a boy, an image he saw led him to seek information on the type of people who accessed such sites.

He said he had not paid any fee and added: "I thought I had deleted them. It was purely for research, there was never any sexual gratification involved."

Mr Hudson said Hooson was at present suspended from work and anticipated being sacked. His involvement with the scout movement has now ended.

Mr Hudson said there was never any question, after police investigations, of inappropriate behaviour during his involvement with the scouts, and asked the judge to suspend any prison term.

But Judge Andrew Gilbart QC said he could not suspend the five-month prison term because of the seriousness of the case, and he also passed orders disqualifying Hooson from working with children and from owning equipment capable of downloading images apart from computers used for work.

Hooson's name is on the sex offenders register for seven years.

A Scout Association spokesman said: "He has betrayed the trust placed in him by parents, by other volunteers and by the Scout Movement."

A spokesman for the county council said: "Police have confirmed that the images were only found on his computer at home."