Updated at 4:02 p.m. EDT
Shares of BP PLC closed down Thursday as the company's CEO told a congressional panel he was "devastated" by the Gulf oil spill and promised again to pay all legitimate claims.
The shares jumped nearly 2 percent before easing back to $31.71, down $0.14 from the previous day.
Special Section: Disaster in the Gulf
that the April 20 explosion aboard a rig operated by BP never should have happened, but he said it was too early to know the cause. The accident killed 11 workers and left a gaping well that's still spewing oil into the Gulf.
BP agreed Wednesday to set up an independently run $20 billion fund to pay damage claims. Hayward told lawmakers the move means Americans can be assured that the company will meet its promise to pay all legitimate claims.
"We're a strong company," Hayward said, "and no resources will be spared." He vowed the company would emerge stronger and safer.
Panel members are questioning Hayward aggressively about whether BP cut safety corners before the blowout on the Gulf floor a mile below the Deepwater Horizon drilling rig.
BP's shares have fallen about half since the Gulf accident.
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