SNOQUALMIE, Wash – A tire fell off a semi-truck again Wednesday, a situation that has repeated itself in just over a month in Western Washington with dangerous and deadly results.

The Washington State Patrol says a 1998 Freightliner owned by Agri-Pac Trucking in Royal City, Wash. was traveling westbound on I-90 near Snoqualmie when it lost a rear tire from the semi trailer.

The axle dropped to the ground and did some more damage to the trailer.

Fortunately, the tire rolled onto the shoulder without hitting anyone.

Troopers on the scene say the wheel had cracked and fell apart, eventually working loose from the axle.  Troopers say that caused the wobbling tire to fall off.  They also say the brakes were not properly adjusted.

The driver, a 47-year-old Royal City man, was cited for defective equipment.

While the state patrol says this is an isolated incident, it's the latest case of tires falling off commercial vehicles since May.

On May 11, a 31-year-old Bothell man died when a wheel assembly fell off a truck on northbound I-5 in Tukwila.  The tires bounced into the southbound lanes, hitting a van and killing the passenger.

Four days later, several cars were struck by a tire that fell off a dump truck on Highway 202 near Fall City.

On May 30, a truck lost two tires on I-90 near Lake Sammamish.  One hit another car, the other bounced onto the roof of a nearby home.

The next day, a truck traveling on Northbound I-5 near Boeing Field lost a pair of tires which harmlessly bounced to the shoulder.