Driver Orders Everybody Off School Bus Minutes Before It Bursts Into Flames And Explodes

A Florida school bus driver was able to empty his crowded bus just before it burst into flames and exploded, witnesses said.

Grateful parents said the driver stopped the vehicle full of schoolchildren after occupants smelled smoke. 

Read: Driver Arrested in Death of Autistic Boy Left on School Bus All Day

Doug Alexander said the driver told him the smell was coming from the air conditioner.

"All of a sudden, ka-boom, the was one explosion and then a few minutes later, another explosion," he said. 

Bystander video sent to CBS affiliate WKMG-TV showed flames billowing from the empty bus and then and thundering booms.

Read: 28 Students Injured, 5 Seriously, When School Bus Overturns

Orlando-area sheriff's deputies said the driver experienced mechanical problems not far from the first stop on his middle school out.

After he herded everyone out, another bus was sent to get the kids home.

Dad Sean Rogers went to pick up his 14-year-old daughter at the explosion site and said he'd like to tell the driver, "thank you very much for saving all those children's lives."

Watch: 6-Year-Old Girl's Shoes, Pants Shredded After School Bus Drags Her Almost a Mile