Police activity on the Dolphin Expressway (State Road 836) eastbound slowed traffic Wednesday morning.
At around 6:15 a.m., police vehicles blocked off some lanes between the area of NW 72nd Avenue and NW 57th Avenue.
An officer could be see shining his flashlight into the water below the bridge.
"The call was received as an assist for the City of Miami, reference an individual that may have run across the road and jumped in the water," the Miami-Dade Fire Rescue said.
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Police were able to make contact with the person, but it was not immediately clear if they were injured.
Drivers are advised to seek an alternate route.
This is a developing story. Refresh for updates.