A 26-year-old Carmarthenshire man is set to go before a crown court judge accused of making and distributing indecent images on children while in Ammanford.
Michael Charles Coker, of Flat 4 Llys Newydd in Llwynhendy, faces four charges.
He is accused of making 16 indecent images of children on October 24, 2010.
Making images refers to the downloading and viewing of images from the internet on a computer.
The second charges relates to the distribution of three indecent child images and the attempted distribution of 136 more on December 13, 2012.
Coker is also accused of possessing 412 indecent images of children on May 10, 2014.
In addition, he faces a single charge of possessing one prohibited image of children on May 10.
No pleas were entered.
District Judge David Parsons, sitting at Llanelli magistrates court, was told that the allegations centred on offences said to have occurred in Ammanford and involved the discovery of 437 on a personal computer and a further three images on a laptop.
Ellie Morgan, prosecuting, told the court that of the images discovered by police, 49 were considered Category A – the most serious level of indecent images – and 28 were Category B.
Many of the images depicted young boys involved in sexual acts with adults, Ms Morgan said.
Mr Parsons told Coker that the offences were so serious the case could only be heard at Crown Court.
Coker was bailed with the condition that he was not permitted any unsupervised access to children under 16.
He is due to appear before Swansea Crown Court on Friday, November 21, for a plea and case management hearing.
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