Last month, U.S. regulators suggested there were new regulatory violations uncovered during an analysis of the Deepwater Horizon oil rig explosion last year in the Gulf of Mexico.
The U.S. Bureau of Safety and Environmental Enforcement announced it notified BP of five regulatory violations stemming from operations at the Macondo well, which failed and caused an explosion that led to the oil spill.
The BSEE said BP failed to conduct integrity testing of parts of a liner. Four violations were issued because the agency found BP failed to suspend drilling operations at Macondo even after safety measures outlined in its application to work there weren't maintained.
"Further review of the evidence demonstrated additional regulatory violations by BP in its drilling and abandonment operations at the Macondo well," BSEE Director James Watson said in a statement.
A U.S. government investigation into the accident concluded BP, Transocean and Halliburton committed a series of regulatory violations at the site. An October report listed seven violations for BP and four each for Transocean and Halliburton.