Admiral Thad Allen says Top Kill appears to be successful UPDATE: Top Kill halted Thursday, restarted Friday

Coast Guard Admiral Thad Allen told reporters Thursday morning that the Top Kill procedure was successful.

The Top Kill procedure pumps heavy drilling mud into the well to stem the flow of oil. Once the oil flow is stopped, then they can pump concrete in to permanently seal the well.

That Allen’s comments to reporters:

The so-called “top kill” effort, launched Wednesday afternoon by industry and government engineers in Houston, has pumped enough drilling fluid to block all oil and gas from the well, Allen said. The pressure from the well is very low, but persistent, he said.

Once engineers have reduced the well pressure to zero, they will begin to pump cement into the hole to entomb the well. To help that effort, he said, engineers are also pumping some debris into the blowout preventer at the top of the well.

Allen said one ship that was pumping fluid into the well has run out of the fluid, or “mud,” and that a second ship is on the way. He said he was encouraged by the progress.

“We’ll get this under control,” he said.

Update: BP stopped pumping drilling mud for about 18 hours to analyze the results.  On Friday, they have tried a junk shot (shredded rubber and golf balls) and then began pumping drilling mud again.