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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Mainly dry with lengthy clear spells overnight and just a few showers likely, especially in the north and west.
Ysgol Uwchradd Caergybi became the UK's first comprehensive 65 years ago. Academies are now dominant in England, but certainly not in Wales.
Dry for most, but a few showers likely.