SANTA FE SPRINGS (CBS) — Two California Highway Patrol officers were injured Wednesday night when a DUI suspect rear-ended their stopped patrol car on the 605 Freeway in Santa Fe Springs, authorities said Thursday.

The officers were rear-ended by a pickup truck at 11 p.m. Wednesday on the northbound 605 Freeway, just south of Interstate 5, according to the CHP.

The officers were transported to hospitals by Santa Fe Springs firefighter-paramedics, a Downey Fire Department dispatcher said.

The CHP officers had stopped on the shoulder to assist another motorist, authorities said.

The CHP investigation closed parts of the 605 for more than four hours, CHP Officer Anthony Martin said.

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