New Orleans ? While BP is capturing more oil from its blown-out well with every passing day, scientists on a team analyzing the flow said Tuesday that the amount of crude still escaping into the Gulf of Mexico may be considerably greater than what the government and the company have claimed.

Their assertions — combined with BP’s rush to build a bigger cap and its apparent difficulty in immediately processing all the oil being collected — have only added to the impression that the company is still floundering in dealing with the catastrophe.

The cap that was put on the ruptured well last week collected about 620,000 gallons of oil on Monday and another 330,000 from midnight to noon on Tuesday and funneled it to a ship at the surface, said Coast Guard Adm. Thad Allen, the government’s point man on the crisis. That would mean the cap is capturing better than half of the oil, based on the government’s estimate that around 600,000 to 1.2 million gallons a day are leaking from the bottom of the sea.

The undersea efforts came as BP Chief Operating Officer Doug Suttles struck an upbeat tone about the anticipated progress of the oil containment in the next week. Suttles told The Associated Press in a stop in Alabama that the arrival of a second vessel in the coming days to help pump the oil from the deepwater gusher could help engineers make even more progress, even as others continued to criticize BP over its handling of the disaster.

A team of researchers and government officials assembled by the Coast Guard and run by the director of the U.S. Geological Survey is studying the flow rate and hopes to present its latest findings in the coming days on what is already the biggest oil spill in U.S. history.

In an interview with The Associated Press, team member and Purdue University engineering professor Steve Wereley said it was a “reasonable conclusion” but not the team’s final one to say that the daily flow rate is, in fact, somewhere between 798,000 gallons and 1.8 million gallons.

“BP is claiming they’re capturing the majority of the flow, which I think is going to be proven wrong in short order,” Wereley said. “Why don’t they show the American public the before-and-after shots?”

He added: “It’s strictly an estimation, and they are portraying it as fact.”

Other members of the team also told AP they expect their findings to show higher numbers than the current government estimate, but they weren’t ready to say how much higher.

To install the containment device snugly, BP engineers had to cut away the twisted and broken well pipe. That increased the flow of oil, similar to what happens when a kink is removed from a garden hose.