OKLAHOMA CITY (Reuters) - Aubrey McClendon, the former chief executive of Chesapeake Energy Corp, was driving well above the speed limit at roughly 88 miles (142 km) per hour before he slammed into a bridge abutment earlier this month and died, Oklahoma City police said on Monday.

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The death of the energy entrepreneur on March 2 shocked the oil and gas industry less than a day after he was indicted by the U.S. Department of Justice on allegations of violating antitrust rules by rigging bids for land. He denied the charges.

Just after the indictment, McClendon’s largest investor, the private equity fund Energy & Minerals Group of Houston, halted all new business with him, depriving him of a key source of funding.

McClendon was traveling above the 50 mph speed limit before he collided with the bridge, causing his vehicle to rotate seven feet (two meters) counter-clockwise, Oklahoma City Police Chief Bill Citty said at a press conference to release findings from the accident investigation.

McClendon’s car collided with the bridge at 78 mph, slowing down after three wheels left the roadway for the dirt shoulder.

A toxicology report and official cause of death would take several more weeks at least, he said. The fatal accident has raised questions about whether the executive took his own life.

McClendon, who was driving his natural gas-powered Chevy Tahoe, was not being pursued and was not chasing anyone, Citty said.

While he was not wearing a seatbelt, such a precaution would not have mattered given McClendon’s rate of speed, Citty said.

“Him not wearing a seatbelt made absolutely no difference,” he said.

McClendon suffered multiple blunt force trauma to his head and torso and likely was dead before a fire engulfed his vehicle and charred his body, Citty said.

The former Chesapeake co-founder did tap his brakes twice after he drove 189 feet left of the center lane, but the actions did not slow his vehicle down. McClendon did not touch the brakes at all in the 31 feet before hitting the bridge, Citty said, citing data retrieved from the Tahoe’s black box data recorder.

“I’m not going to speculate on what that tapping of the brake could mean. It could mean a lot of different things,” Citty said.

Oklahoma City police are pulling McClendon’s phone records and interviewing family members and friends as part of the ongoing investigation before the case is turned over to the medical examiner, Citty said.