A crash involving a tractor-trailer has closed northbound lanes of Route 28.
The crash occurred around 8:15 p.m. near the Route 8 exit, authorities said.
State police in Kittanning said the driver of the truck is in critical condition, while two passengers in a car are listed as having moderate injuries.
Police are detouring motorists at either exit 5A -- the southbound Route 8 ramp toward Sharpsburg -- or exit 5B -- the northbound Route 8 ramp toward Butler, PennDOT spokesman Steve Cowan said.
Motorists are being advised to take alternate routes.
Lexi Belculfine: firstname.lastname@example.org or 412-263-1878. Twitter: @LexiBelc.