Executives from BP and its partners in the disastrous oil rig explosion in the Gulf of Mexico were grilled Tuesday by Senators, who expressed frustration at the company officials’ shifting of blame and their inability to pinpoint the cause of the incident.

“We are here today because of a disaster that never should have happened,”said Sen. Jeff Bingaman (D-N.M.), chairman of the Energy and Natural Resources Committee, one of two panels that held hearings on the issue Tuesday. “I don’t believe it is enough to label this catastrophic failure as an unpredictable and unforeseeable occurrence.”

Sen. Lisa Murkowski, ranking member of the Energy and Natural Resources Committee, chided the executives for pointing fingers at each other. The Alaska Republican reminded them “that we are all in this together.”

The companies have clashed over whether a piece of the machinery, called the “blowout preventer,” or improper cementing of the well failed to prevent the well rupture.

Lamar McKay, president of BP North America, told the panel that it was essential to find out what went wrong with the blowout preventer, which is owned by another company, Transocean. But in written testimony, Transocean’s Steven Newman denied the blowout preventer could be the main culprit and instead noted that the cementing of the well should have prevented the rupture.

The cementing was done by Halliburton. But Tim Probert, Halliburton’s president for global business lines, told the panel that his company had done the cementing of the well in accordance with directions provided by the well operator, BP. He also said that Halliburton “was contractually bound to comply with the well owner’s instructions on all matters relating to the performance of all work-related activities.” BP is the well owner and general operator of the oil exploration project.

Sen. John Barrasso said the companies involved in the oil spill appear to be trying to dodge blame for the incident.

“Shifting the blame doesn’t get us very far,” the Wyoming Republican said.

Sen. Bob Menendez (D-N.J.) said judging from statements from BP, Transocean and Halliburton, “I can already see the liability chase going on.”

Sen. Jeff Sessions (R-Ala.), whose state’s coastline could be affected by the spill, said he had been a longtime supporter of offshore drilling, but he added that past success in the Gulf of Mexico may have led to complacency and overconfidence.

Meanwhile, Sen. Mary Landrieu (D-La.), whose state has been hard hit by the oil spill, asked McKay bluntly: “Will BP pay” to defray costs of those impacted by the spill?

“We are going to pay all legitimate claims,” McKay responded. He said the company would exceed the $75 million cap on liability claims for oil pollution spills.

But Sen. Ron Wyden (D-Ore.) accused BP of having a management culture that has led to “one accident after another.”

“I believe we are changing this company,” McKay said.

BP also came under fire from Menendez, who said the company appeared to be “flailing around” in trying to plug the well. “I get the sense you are making things up as you go along,” Menendez said.

McKay declined to say if he would support legislation proposed by Menendez and several other lawmakers to raise the liability caps from $75 million to $10 billion.

The BP executive said he had not had the time to review the legislation.

The corporate executives, seated at a witness table before the Senators, expressed sadness about what had happened.

“I sit before you with a heavy heart,” Newman told the panel. He noted that nine of the 11 people who have been reported missing and are feared dead in the explosion worked for Transocean.

The three executives were later expected to testify before the Senate Environment and Public Works Committee.