The man was arrested in Ipswich this morning.
The Serious Organised Crime Agency says it is the first arrest as part of Operation Pallial, which last November started investigating recent allegations relating to historic child abuse in North Wales.
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The three-day event in the Welsh capital is expected to attract more than 20,000 visitors.
Steve Ashton's picture of a jacket potato and corned beef served to his 81-year-old mother has been shared 130,000 times on Facebook.
The Welsh Conservatives pledged 'continued economic recovery' as they launched their manifesto in Builth Wells this afternoon.