Some sort of industrial accident was to blame on Tuesday afternoon when the driver of a big rig hauling very large beams was killed.
The incident occurred shortly before 3 p.m. on Interstate 8 east in East County, according to the California Highway Patrol.
The blue single-cab Peterbilt truck came to a stop in the No. 1 lane of the freeway not far from Harbison Canyon, east of El Cajon.
From video shot by NBC 7's SkyRanger 7, the tractor-trailer appears to have been hauling some sort of very large beams that apparently shifted forward and into the back of the truck's cab, impaling and killing its driver.
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The name of the business operating the vehicle is not yet known.
No one else was harmed by the incident, according to the CHP, which said at 4:45 p.m. that traffic on I-8 eastbound had backed up all the way to Mollison Avenue in El Cajon and was urging drivers to avoid that stretch of freeway if possible.
It is unknown if drugs or alcohol are a factor in this crash, the CHP said in a news release issued later on Tuesday afternoon.