I-35 south of Dallas Zoo blocked by overturned 18-wheeler

Nearly all southbound lanes of I-35 near the Dallas Zoo were blocked by an overturned 18-wheeler Wednesday evening.

I-35 18-wheeler crash

What we know:

As of 8:15 p.m. Wednesday, only one southbound lane was open on I-35 at Zang Boulevard, and cars were moving past very slowly. 

TxDOT traffic cameras show traffic backed up for some distance behind the crash.

What we don't know:

The cause of the turnover is unknown at this time. 

No estimate for when it will be resolved has been released. 

FOX 4 has reached out to Dallas officials for comment on the incident. 

The Source: Information in this article comes from TxDOT traffic footage. 

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