The NCA said suspects include doctors, teachers, Scout leaders, care workers and former police officers. In total, only 39 registered sex offenders are among those arrested.
Officers have searched 833 properties and examined 9,172 computers, phones and hard drives.
The NCA said it built up "intelligence packages" on suspects and sent them to police forces across Britain.
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The study is expected to warn of the impacts of melting ice and permafrost.
Some northern and eastern areas may stay bright and warm but heavy rain or showers will affect most parts.
Police used tear gas and rubber rounds against protesters on Saturday