Published: Jul 13, 2010 12:43 AM EDT
Updated: Jul 12, 2010 9:43 PM EDT

NEW ORLEANS (AP) - Live underwater video showed a new cap was placed Monday onto the leaking well in the Gulf of Mexico, offering hope of containing the gusher for the first time since BP's deepwater rig exploded in April.

BP officials did not immediately comment on the video images streamed online by the company. The company has said the next step will be running tests to make sure there are no other leaks from the well. Tests and monitoring could last from six hours to two days, and oil will still leak into the Gulf during that time.

The old cap, removed Saturday, did not have a tight fit and allowed crude to escape.

The cap is only meant to be a temporary fix. To permanently plug the well, BP is drilling two relief wells to reach the blown-out well from underground and inject heavy drilling mud and concrete.  BP expects one relief well will do the job, but it's drilling a second as a backup. Officials have offered varying estimates for when that work will be done, but mid-August is the most common timeframe.