A railway guard who encouraged young girls to send him indecent pictures of themselves has been jailed for five years and four months.

Paul Marshall, 61, showered the youngsters with gifts as well as buying them booze and cigarettes as he groomed them for his vile purposes.

And as well as getting the girls, aged 14 and 15, to send pictures in states of undress he also encouraged them to go to a dogging site with him and strip off for money.

Marshall's depravity was only uncovered after another girl made a complaint that he had offered to take her ice skating after chatting to her on a train.

Hannah Squire, prosecuting, told Swindon Crown Court on Friday when police arrested him for that, which was not proceeded with, they examined his computer and diaries.

In them they found a number of pictures of the underage girls along with series of entries cataloguing what he had done to them.

The first girl was just 15 when she met Marshall through friends in the spring of 2009, befriending him as he would buy her alcohol and cigarettes.

He would also take her shopping, buying her clothes and other gifts, and paid for her to get a tattoo, despite her being underage.

After he a while he started insisting she send him pictures of herself, for his generosity to continue, first in her underwear, then topless and naked.

In his diary he spoke of trying to take her to a notorious dogging site near Bath, and even made reference to her turning 16 proving he knew her age.

In a text message, accidentally sent to the girl's mum, he said, "Take on board what I say. The more you give the more you get treats. You need to make more effort".

Miss Squire said the second victim, a 14-year-old, approached him around the same time after learning through friends he bought things for teenage girls.

He gave her similar gifts and paid her £80 to sunbathe topless for him, she refused £100 to go nude.

In one diary entry in June 2009 he wrote, "Meeting her at 1830 at Tesco Express. Seems to be up for anything. Will have sex for money. What a lovely pretty girl".

He also showed her some of the 116 indecent images of the other girl as he encouraged her to send some of her, which she did 27 times.

As well as the pictures being found on his computer he had also printed some out and they were kept in his bedroom.

Marshall, of Rutland Close, Melksham, admitted two counts of meeting a child after grooming and six of making indecent images of a child.

Miss Squire said as a result of the offending both children felt trapped and unable to tell leaving them psychologically damaged.

Alex Daymond, defending, said apart from the offending in his mid 50s his client had never been in any sort of trouble before.

"Why it has happed is a mystery to him and a mystery to other people as well," he said.

"He realises it is probably worth very little but he apologises to the girls for what he has done."

Jailing him Judge Tim Mousley QC said: "You systematically groomed these two young girls over a period of time.

"It is quite clear what you had in mind in behaving in the was you did towards them.

"Putting it mildly you gave caused them enormous, perhaps incalculable, distress. You have caused each of them great harm. There are two ruined lives at least."

As well as jailing him, the judge said Marshall must register as a sex offender for life and imposed a sexual offence prevention order restricting his liberty when he is released.