At a news conference, Odessa Police Chief Michael Gerke said three law enforcement officers were among those wounded in the shooting spree. The shooter left his own vehicle and hijacked a mail truck before authorities caught up to him in the parking lot, according to reports.
Gerke identified the suspect as a white male in his 30s but provided no name or likely motive.
Midland Mayor Jerry Morales told CNN the spree began when a Department of Public Safety trooper pulled over the suspect's vehicle on an interstate on Saturday. The reason for the stop is unclear.
The incident is the second Texas mass shooting this month. In early August, another gunman killed 22 people in an El Paso Walmart after authorities said he posted a racist screed about protecting the state from a "Hispanic invasion."
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