Lee Miles of the National Cyber Crime Unit (NCCU) has said his agency is working with international Partners to find the source of the malicious emails:
The NCA are actively pursuing organised crime groups committing this type of crime.
We are working in cooperation with industry and international partners to identify and bring to justice those responsible and reduce the risk to the public.
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Philip Hammond has dismissed concerns that abolishing stamp duty for first-time buyers will push up house prices.
Elsewhere it will be largely sunny, though with gusty winds at times, and a few showers likely in places.
Heavy rain has caused widespread flooding and travel disruption across north west England and North Wales.