HOUSTON May 26 (Reuters) - BP Plc (BP.L) (BP.N) Chief Operating Officer Doug Suttles said on Wednesday it appears drilling mud, not oil, was gushing from a ruptured undersea well six hours into an effort to halt a month-old oil spill.
"What you've been observing coming out of the top of that riser is most likely mud," Suttles said at a news conference broadcast from a Louisiana command center. "We can't fully confirm that because we can't sample it. And the way we know we've been successful is it stops flowing." (Reporting by Bruce Nichols and Erwin Seba)