Police officers were called to North Bridge at 1.42pm today (Friday) after receiving reports of a concern for safety of a woman.
The A58 Burdock Way is also blocked in both directions with stationary traffic around Haley Hill.
Police and traffic officers are currently at the scene diverting traffic.
Delays are starting to build on the surrounding roads.
Firs West Yorkshire buses said the closure is affecting Bradford Services with the severe traffic disruption in the area causing delays of up to 30 minutes to services.
It is not known when the road will re-open.
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