It happened on US-290 near Barker Cypress and Skinner Roads just before 1 a.m.
The METRO police officer arrived to the scene of an earlier crash and was diverting traffic in the westbound lanes of the freeway, authorities said.
Less than three minutes after arriving, another car collided into the METRO cruiser.
There were no major injuries reported in the crash, though the main lanes were closed Friday morning.
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