NEAR HAZEL DELL, Wash. - Police say a tired truck driver drove his semi into the back of another big rig on Interstate 5 northbound near Hazel Dell early Monday morning.

Police closed one lane of the highway while investigating the collision, which took place at about 4 a.m.

One of the truck drivers was taken to a hospital with back pain. No other injuries were reported. One truck ended up jack-knifed against a concrete barrier.

Another had damage to the trailer it was pulling.

Police said one driver may have fallen asleep at the wheel and caused the collision.

Crews had to soak up a minor oil spill at the site before lanes were reopened in time for the heavy morning commute.