MOUNT PLEASANT TOWNSHIP, Pa. — A huge pileup involving two tractor-trailers, a tour bus and passenger cars killed five people and injured at least 60 others in western Pennsylvania Sunday morning, authorities said.
The crash happened around 3:34 a.m. on the Pennsylvania Turnpike in Mount Pleasant Township southeast of Pittsburgh, the Westmoreland County Department of Public Safety said.
The Pennsylvania State Police said the tour bus was traveling on a downhill curve when it struck an embankment. Commercial vehicles following behind then struck the bus, state police said.
Westmoreland County Department of Public Safety said there were no indications of bad road conditions.
"Crash involves 2 tractor trailers, a tour bus and passenger vehicles. Turnpike is closed in both directions from New Stanton (#75) to Breezewood (#161). A prolonged closure likely," Pennsylvania Turnpike spokesman Carl DeFebo tweeted.
The National Transportation Safety Board will investigate the crash.
Five hours after the crash, an 86-mile stretch of the turnpike remained closed, DeFebo said.
The five people killed were found dead at the scene, county coroner Ken Bacha said.
About 60 patients were taken to three area hospitals, DeFebo said.
Excela Frick Hospital received 25 patients ranging from ages 7 to 52, spokeswoman Robin Jennings said. She said nine of the patients are children.
Eleven patients aged 15 to 67 were taken to Forbes Hospital in Monroeville, Pennsylvania, hospital spokeswoman Stephanie Waite said. Two patients were in critical condition and nine were in fair condition, Waite said.
UPMC Somerset received 18 patients -- 12 adults and six children, hospital spokesperson Sarah Deist told CNN. All 18 were treated and released, she said.
The crash occurred in Mount Pleasant Township southeast of Pittsburgh.
Pennsylvania Turnpike Public Information Manager Rene Colborne said the speed limit is 70 mph in the crash area. The road conditions seemed to be "fine" and the roads are treated 24/7, she said.
Images of the crash site show a tour bus lying on its side, with several damaged tractor-trailers, including a FedEx truck, splayed around it across the roadway.
FedEx spokeswoman Allie Addoms provided this statement: "First and foremost we extend our deepest condolences to the families of the individuals involved in this accident. There is no higher priority for FedEx Ground than safety, and we are cooperating fully with investigating authorities at this time."
A UPS spokesman said that one of its vehicles was involved in the crash and issued the following statement: "UPS is cooperating with authorities in the investigation and we express our deepest sympathies to the victims and their families and friends."
The National Transportation Safety Board is sending a team of more than a dozen people to the crash site to investigate, the agency announced in a tweet.
Major pileups have occurred on the Pennsylvania Turnpike in the past. In February 2014, 100 vehicles were involved in a massive wreck north of Philadelphia that injured at least 30 people.
CNN's Lechelle Benken and Ralph Ellis contributed to this report