MIAMI -- The driver of a bus that crashed into an overpass at Miami International Airport apparently got lost in the moments before the collision, plowing into the flyover despite several signs warning vehicles over 8-feet, 6-inches to stop and turn left.

Two people were killed and three others critically injured in the accident, which crushed the top of the bus.

"It appears that the bus driver was not familiar with the area and somehow ended up in the area of the airport," said Miami-Dade police spokeswoman Lt. Rosanna Cordero-Stutz. "Because he was unfamiliar with the airport, [he] apparently ended up in a drive with an overpass that did not have clearance for his bus."

The coach, carrying 32 passengers, was going about 20 mph when it struck the overpass, according to airport spokesman Greg Chin. Buses are supposed to go through the departures area because of its higher clearance, he added.

NBCMiami.com reported that the driver wasn't injured.

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Police identified the two men killed as Serafin Castillo, 86, and Francisco Urana, 56, both of Miami, police said. The bus was bringing the group of Jehovah’s Witnesses to a gathering in West Palm Beach. No charges have been filed while the investigation takes place, police said.

One survivor told NBCMiami.com how he tried to help fellow passengers escape the vehicle.

"I felt my own blood trickling down, but that didn't worry me,” said passenger Luis Jimenez, who injured his hand and lip in the accident. "I could walk, and I could try to help others."

Tour bus hits Miami airport overpass

He was in the second to last row of the bus when the collision occurred.

"I would tell them, ‘Stay calm. Stay calm. Help is on the way,’” Jiminez added. 

Wilfredo Lee / AP

Workers and law enforcement officers prepare to remove the charter bus that hit a concrete overpass at Miami International Airport on Saturday. The coach was too tall for the 8-foot, 6-inch entrance to the arrivals area.

“We are praying for all those people who are ill and injured. It was not our intention. It was an accident. It wasn’t the driver’s intention,” said Mayling Hernandez of the Miami Bus Service who owned the bus. Federal Motor Carrier Safety Administration records found online show the company has had no violations for unsafe driving or controlled substances and alcohol. It also had not reported any crashes in the two years before Oct. 26, 2012.

The driver, Ramon Ferriero, who was unhurt in the crash, "is feeling bad," she said.  Ferriero couldn’t be reached for comment Sundahy.

"The airport is under construction, everything has been moved and maybe he got lost and something happened," Hernandez said.

NBCMiami.com's Gilma Avalos and Juan Ortega and The Associated Press contributed to this report.