If you are headed to Baytown from downtown Houston, be aware that traffic is already backing up.
We do not yet know how the accident happened, or the condition of the officer involved.
SkyEye video shows an officer being taken away from the scene on a backboard.
Katherine Whaley said you can take Market Street or the feeder road as an alternate.
We're following this story on Eyewitness News. Watch for updates on air, online and on our mobile news app.
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