PITTSBURGH (KDKA) – A motorcyclist is dead following an accident that closed the Squirrel Hill Tunnel.

A motorcycle hit the jersey barrier in the outbound lane on Friday, prompting the closure of both inbound and outbound I-376 for the three-vehicle accident involving a box truck, truck tractor and the motorcycle, the state police said.

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Officials said the motorcyclist was pronounced dead on the scene.

The motorcyclist struck the rear end of the box truck, causing the bike and operator to go underneath a flat semi-trailer being pulled by a truck tractor.

Both lanes have reopened as of 1:50 p.m.

WATCH: KDKA’s Paul Martino reports live from the Squirrel Hill Tunnel.

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The motorcycle was reportedly leaning up against the jersey barrier.

Police and medics are on scene, and the motorcyclist will be transported to the hospital.

Outbound traffic is being detoured at the Squirrel Hill/Homestead off-ramp.

If you’re heading towards the Squirrel Hill Tunnels, you should consider an alternate route.

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Stay with KDKA for the latest on this developing story.