Jerusalem (CNN) -- The official limousine awaiting President Barack Obama's arrival in Israel malfunctioned after its driver refueled it using gasoline rather than diesel fuel, an official said Wednesday.
The limo failed to start, and required towing in Jerusalem at 10 a.m. local time. Obama, who landed in Tel Aviv around noon, was not in the country at the time the limo was towed. A second presidential limo was brought to transport Obama.
"We experienced mechanical trouble with one of the cars," Edwin Donovan, a spokesman for the Secret Service, told a pool reporter traveling with Obama. "We don't know the cause."
Donovan couldn't confirm reports the limo was refueled using gasoline rather than diesel.
"That's why we bring different multiple vehicles," Donovan said.
The tow truck company owner who picked up the limo said the U.S. consulate called him to tow the vehicle in Jerusalem because it wouldn't start.
Multiple official vehicles are typically flown ahead of time to destinations where Obama is visiting. On his trip to the Mideast, Obama will stop in Tel Aviv and Jerusalem in Israel, Ramallah in the West Bank, and will visit with Jordan's King Abdullah in that nation.
The presidential limousine, known as the "Beast," is a specially built Cadillac that's estimated to weigh 8 tons. There are multiple, identical copies that are used to transport Obama around Washington and on his trips out of town.
The Secret Service is tight-lipped about the specifics of the vehicle, but the car reportedly features inches of armor and bulletproof glass, doors and windows that seal shut in the event of a gas attack, and special shocks to absorb blasts.
It's said to be built on a medium-grade truck chassis, the Chevrolet Kodiak, which runs on diesel fuel.
Diesel engines differ from gas engines in the way the internal combustions are created to drive the pistons. Diesel engines utilize compressed air to generate heat that causes the fuel to ignite. Gas engines ignite fuel using spark plugs.
Using gas instead of diesel could cause major damage to the pistons, wrist pins and connecting rods, which would be destroyed if the fuel is ignited at the wrong time.
Gasoline is also less viscous than diesel, which acts as a lubricant for the fuel pump and fuel delivery systems. Those parts could also be destroyed if gasoline is pumped into a diesel engine.
CNN's Kevin Liptak contributed to this report.