A LEX Illini Express van tipped over during a storm South of Matteson, Illinois during strong storms Saturday

The van, carrying two passengers at the time of the accident, pulled over to the side of the road due to strong rain, said Robert Frazier, President of LEX Illini Express.

"We've never run into an F4 tornado before," said Frazier. "(The storm) was quite unforeseen, came up quickly and there was no way of predicting that it would become an F4."

"It's always a judgement call as to when you should go," said Frazier. "We always have taught drivers that if the weather looks bad they should pull over to the side of the road. Unfortunately, customers complain about sitting."

After the accident passengers were taken to the hospital and the passengers were treated for cuts and bruises Frazier added.

"Customers should understand that we were concerned with their safety." Frazier said. "I think we got very lucky."