Contractors hit back at BP oil spill report

BP's investigation into the Gulf of Mexico spill sparked a backlash from its contractors and US politicians who accused the oil giant of attempting to shift some of the blame.

The internal inquiry, led by the company's head of safety and operations, Mark Bly, found BP was responsible in part for the tragedy, but also pointed the finger at rig owner Transocean and cement contractor Halliburton.