GIG HARBOR, Wash. - Thick fog and icy roads were blamed for a 20-car pile-up Saturday morning that blocked the eastbound lanes of Highway 16 near Gig Harbor for hours Saturday morning.

The chain-reaction crash involved more than 40 people, but only seven of them were hurt badly enough to be taken to the hospital, fire officials said.

A spokesman for the Gig Harbor Fire District said a car entering Highway 16 at the Wollochet on-ramp sparked the chain reaction at about 10 a.m. Drivers reported that fog and speed contributed to the collision.

Firefighters and paramedics had responded to two other crashes in the same section of Highway 16 within less than an hour before the 20-car pile-up.

Motorists told police and fire officials that they suddenly saw red taillights in the dense fog and tried to stop.

One woman said she managed to stop without hitting the car in front of her, but the car behind her did not stop. It smashed into the rear of her car, shoving the line of cars forward.

She said there were already several other cars off the road in front of her.

Dozens of emergency units responded to the scene of the pile-up, including state troopers, Gig Harbor police, several tow trucks and medic units from Gig Harbor Fire, University Place Fire, Key Peninsula, American Medical Response and Rural Metro.

Cars were detoured around the crash scene at Wollochet Drive, and two lanes of Highway 16 were reopened at 11:30 a.m., but it still took another hour to clear the five-mile-long backup.

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