British travel company Thomson is facing a barrage of criticism after a data protection breach released home addresses, names and flight information of more than 450 customers. The data was accidentally sent out in an email that was quickly recalled, the company said in a statement.

Thomson apologized for the “genuine error,” but said travelers whose information was exposed would not receive any compensation for the mistake, the BBC reported. “We would like to apologize to our customers involved and reassure them that we take data security very seriously,” Thomson said in a statement. “We are investigating the matter to ensure this situation will not be repeated.” It gave no other details about who was responsible for the incident.

The email with the leaked information was reportedly sent Aug. 15, and contained names, email addresses, home addresses, phone numbers, flight dates and remaining balances due for 458 customers. The company statement said the email was swiftly recalled after employees realized the mistake, and the recall was “successful in a significant number of cases.”

The BBC spoke to several Thomson customers whose information was leaked in the breach, several of whom expressed anger at Thomson’s response. “How can we relax on holiday knowing that 500 people have my address and know when we are going to be away?” customer Karen James told the agency, adding she was afraid someone would sell the information. “An apology is all well and good, but I want to know how this was allowed to happen and how they can guarantee it won’t happen again.”

Thomson handles bookings and travel logistics for flights, hotels and cruises, and specialized travel packages. The company’s Facebook page has a number of recent posts from travelers complaining about poor customer service.