Congressional investigators have published a series of internal BP memos which they say proves that the British company systematically and negligently put safety at risk on the Deepwater Horizon oil rig in order to increase profits.

Confidential e-mails written in the days before the catastrophic explosion in the Gulf of Mexico appear to show that serious concerns, raised within the company and by contractors, were disregarded for financial reasons.

One BP engineer warned a colleague that the oil well had become a “nightmare” while executives were given a list of recommended safety measures which they chose to ignore. One BP official wrote a note that read: “Who cares, it’s done, end of story, will probably be fine.”