HOUSTON (KTRK) -- Authorities say a speeding car struck a police patrol car before careening off the freeway in a horrific wreck.The wreck happened around 4:30pm Wednesday on the southbound lanes of the Eastex Freeway at Kelley, just north of the North Loop. Officials say a car hit the back of a Houston police car and catapulted over the top of the guardrail of the southbound lane. The vehicle landed on its roof in the area below, between the freeways.Three people were inside the vehicle that fell from the elevated portion of the road. Two people were killed instantly, and the third victim died at a local hospital.The HPD officer did not suffer serious injuries.All southbound lanes of the freeway were closed during the police investigation, but have since reopened. Traffic was backed up for miles.