Prosecutor Linda Baker told the court that following a complaint to police, other offensive tweets by Robert Riley came to light.
Among them were messages about the missing Malaysian plane, the Korean ferry disaster and champion tennis player Serena Williams.
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Well a fabulous day today has ended on a spectacularly soggy note for some! Heavy rain, hail and thunder will work northwards overnight!
The Talyllyn runs from Tywyn, near Aberdovey, for more than seven miles to two villages in the south Gwynedd countryside.
Homes in parts of Tonypandy and Llwynypia are without water this evening due to a burst water main at Cilfynydd.