President Barack Obama said Tuesday that if any laws were broken in the Gulf of Mexico oil spill, people will be prosecuted. He dispatched his attorney general to the Gulf and gave marching orders to the leaders of an independent commission investigating the spill 'to follow the facts wherever they lead, without fear or favor.' Obama spoke in the White House's Rose Garden after meeting with the co-chairmen of the commission, Bob Graham, a former Florida governor and Democratic U.S. senator, and William K. Reilly, a former head of the Environmental Protection Agency under Republican President George H.W. Bush. Their task, Obama said: 'To thoroughly examine the spill and its causes, so that we never face such a catastrophe again.' Port Fouchon, Louisiana, Attorney General Eric Holder said federal authorities had begun criminal and civil investigations into the leakage of millions of gallons of crude oil into the Gulf of Mexico. Holder met with the attorneys general of Louisiana, Alabama and Mississippi and several U.S. attorneys. He said several senators have asked the Justice Department to determine whether criminal or civil laws were broken in the spill. The Justice Department has told Sen. Barbara Boxer, who heads the Senate's environment committee, that it has ordered BP PLC, lessor of the destroyed oil rig, not to destroy documents that could be relevant to investigators. 'If our laws were broken, leading to this death and destruction, my solemn pledge is that we will bring those responsible to justice on behalf of the victims of this catastrophe and the people of the Gulf region,' Obama said. He said that if existing laws were insufficient to prevent another such catastrophe, the laws would be changed, and if oversight were inadequate, it would have to be reformed. Obama's session with Graham and Reilly and Holder's visit to the Gulf Coast come three days after BP said its latest attempt to stop the oil spewing out of a broken well under 5,000 feet of water had failed. That latest setback happened not long after Obama held a rare White House news conference devoted mainly to the spill and visited coastal Louisiana to assess the situation and reassure frustrated residents. The administration moved on several fronts Tuesday to assert more control over the catastrophe and distance itself from well operator BP. Administration officials walked a fine line, however, to avoid the harshest criticism of a company it still must rely on to tame the runaway oil well. Also, by claiming more responsibility they opened themselves to more political exposure should the situation in the Gulf continue to deteriorate. The administration put an end to joint news conferences with Coast Guard and BP officials that had been occurring in the gulf. Instead, the federal leader of the response effort, Coast Guard Adm. Thad Allen, will conduct his own briefings. In some of the administration's most direct criticism of BP since the drilling rig it was leasing off the Gulf exploded April 20, White House Press Secretary Robert Gibbs said the oil giant was not forthcoming about the risks involved in the latest tactic for reining in the spill, which has poured at least 20 million gallons of crude into the Gulf. BP is moving forward with plans, approved by the Obama administration, to slice through the damaged riser that is billowing oil and gas and cap it with a containment mechanism. White House Energy Adviser Carol Browner said during the weekend that the approach could result in a temporary 20 percent increase in the flow, a figure Gibbs repeated Tuesday. BP has said it did not expect a significant increase in flow from the cutting and capping plan. 'Do I think that BP was forthcoming on what the impact would be of cutting the riser off? No, obviously,' Gibbs said. But he did not respond directly when asked whether Obama trusts BP. 'We will continue to push BP to do whatever we feel is necessary to respond to the leak,' Gibbs said. Over the weekend Obama said the continued leak 'is as enraging as it is heartbreaking.' Obama seemed more calm than enraged Tuesday but Gibbs assured reporters the rage was there, though he demurred when asked if BP was its target. 'I've seen rage from him. I have,' Gibbs said, describing Obama appearing in meetings with 'clenched jaw' and ordering aides to 'plug the damn hole.' Tuesday's meeting was Obama's first with the independent commission's co-chairmen since he selected them less than two weeks ago. He directed them to report back in six months. Obama still must name five members of the commission, which will investigate such issues as what caused the spill, the safety of offshore drilling and operations at the federal agency that grants drilling rights. Browner said she does not want to guess the prospects for success from the containment cap approach. Interviewed Tuesday on ABC's 'Good Morning America,' the White House energy and global warming adviser said, 'everyone, I think, is hoping for the best, but we continue to plan for the worst.' She said she is concerned about the impact the coming hurricane season could have on ending the environmental crisis. 