A laptop containing personal information of some 13,000 people who filed claims for compensation after last year’s big oil spill in the Gulf of Mexico has been lost, announced the spokesman of oil giant BP.

The laptop contains the individuals’ names, phone numbers, addresses, dates of birth and Social Security numbers. According to the NPR, BP sent out written warnings to each of the affected claimants and offered them free credit monitoring services.

Law enforcement has been notified and an investigation is ongoing. So far, it is known that the laptop was lost by a BP employee while traveling. “If it was stolen, we think it was a crime of opportunity, but it was initially lost,” said BP spokesman Curtis Thomas. He also noted that the laptop was password protected, but that the information was unencrypted.

Nearly a month has passed since the loss of the laptop, but so far, it seems that the lost information has not been misused. BP says that they notified the claimants only now since they had to keep mum about the incident so as not to jeopardize the investigation.

The claimants are obviously not pleased with the situation, and some of them have not yet received the e-mail notification from BP, which was sent out on Monday.