In the video above, you can hear the park ranger telling people they needed to be within six feet distance of each other. As he's talking, he's pushed into shallow water, and the group laughs.
The video, posted on social media, shows the ranger climbing out of the water as the man runs off.
Authorities have identified the suspect as Brandon Hicks.
Police say the crowd was illegally drinking and smoking. City officials say they were "saddened" by the incident.
Although Texas parks have reopened, Gov. Greg Abbott's order says people must keep their distance.
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