The wreck happened on the southbound lanes of I-45 near Cavalcade.
According to Houston police, an off-duty officer riding a motorcycle was struck from behind, and then he hit the deputy's patrol vehicle.
HPD officers are responding to the scene of an HPD officer accident at 45 and Cavalcade. The off-duty officer riding a motorcycle was struck from behind & he then struck an @Pct1Constable patrol vehicle. The HPD officer suffered minor injuries. Please avoid the area #houtraffic— Houston Police (@houstonpolice) December 20, 2018
The southbound side of the freeway is shut down during the investigation.
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