Northwest Fire District spokesman Adam Goldberg says the accident happened shortly after 10 a.m. on westbound I-10 near Tangerine Road. The westbound freeway was closed near that area.
The officer had to be extricated from the DPS sports utility vehicle he was driving. He was transported to a Tucson hospital and is in serious but stable condition, Goldberg said. The driver of the semi was not injured.
The officer had a DPS K-9 with him that appeared to be uninjured. Emergency responders were waiting for another K-9 officer to take the dog.
An investigation is ongoing.
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