The City of London Police arrested a Sage employee today at Heathrow airport on charges of conspiring to defraud the accountancy software maker.
The woman was arrested in connection with an alleged fraud against the firm. She has since been bailed, the statement said.
Over the weekend, it was revealed that the information of nearly 280 UK Sage customers — including employee bank details and salary information — may have been compromised in a cyber attack.
Sage said that an internal login had been used to gain unauthorised access to some of the data. Reports suggest that the company is still trying to establish whether anything was actually stolen.
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"We are investigating unauthorised access to customer information using an internal login," Sage previously said in a statement.
"We cannot comment further whilst we work with the authorities to investigate but our customers remain our first priority and we are speaking directly with those affected," it added.