The personal details of 458 travellers have been revealed after a data breach by holiday company Thomson.
An email (seen by staff at the BBC) that was sent in error has revealed the home addresses, telephone numbers and flight dates of 458 customers.
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According to the BBC, Thomson has apologised for the incident, calling it a "genuine error".
A company statement said: "We are aware of an email that was sent in error, which shared a small number of customers' information.
"The error was identified very quickly and the email was recalled, which was successful in a significant number of cases.
"We would like to apologise to our customers involved and reassure them that we take data security very seriously.
"We are urgently investigating the matter to ensure this situation will not be repeated."
Some customers have been left wondering whether they should cancel their holiday.
One holidaymaker from Cornwall who has flights booked to Lanzarote told the BBC: "My biggest fear is that this list will be sold to someone, because the wrong person could have a field day with this information.
Thomson has apologised but said customers would not receive compensation.
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