LOUISVILLE, Ky. (WDRB) -- A semi crash and fire has shut down the ramp from eastbound Interstate 64 to northbound Hurstbourne Parkway.

It happened about 3:50 a.m. That's when the tractor-trailer veered off the road on the ramp from I-64 to Hurstbourne Parkway. Part of the truck was left hanging over a concrete barrier wall.

The cab burst into flames. Witnesses tell WDRB News that the flames shot 15 feet into the air. We spoke with the driver, who says he is shaken up but feels lucky to be alive.

An eyewitness told us construction crews working nearby sprang into action as soon as the truck crashed, and managed to free the driver just before the cab caught fire.

Armani Valentino told us he ran to a nearby building to get a fire extinguisher while his colleagues helped the driver.

"By the time I got back out, the other guys were over there and they were trying to help him get out already. I yelled was he out and they said, 'Yes, get back because this thing is going to blow!' because it was catching on fire so fast.

"And you kept hearing like, gas, and it was blazing up, like every few seconds, it just kept blazing up and blazing up and blazing up. And before you know it, the whole cabin, the whole front cabin of the 18-wheeler was on fire."

Firefighters called their actions heroic.

The tractor-trailer was reportedly carrying U.S. mail from the Gardiner Lane post office. 

Customers who feel their mail may have been affected by the accident and fire should call the Postal Service Call Center at (800) 275-8777 for further assistance.

If a package was insured, a claim can be filed online at www.usps.com/insuranceclaims/online/welcome.htm. Or you may pick up a PS Form 1000 at your local Post Office.

Police say it appears speed may have been a factor in the crash.

The ramp from I-64E to northbound Hurstbourne Parkway was expected to remain closed for several hours while crews worked to clean up the wreckage as well as about 50 gallons of spilled diesel fuel.

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