Paramedics performed advanced trauma care at the roadside after being called to the junction of Station Road and Victoria Road at around 6am.
A spokesperson for West Midlands Ambulance Service said: "“We were called at 6:06am to an incident at the junction of Station Road and Victoria Road in Pelsall. We sent two ambulances, a paramedic officer and the MERIT trauma car with two doctors and a critical care paramedic onboard.
"On arrival, crews found a patient in a critical condition. They carried out advanced trauma care at the scene and continued with treatment en-route to hospital.”
Roads including Station Road, Vicarage Road, Victoria Road and Coronation Road were closed on Wednesdsay morning due to a "police-led incident".
A spokesperson for West Midlands Police said: "We were called to reports that a man had fallen from a bridge over Station Road, Pelsall this morning.
"Emergency services attended the scene at the junction with Victoria Road at around 6.10am. The man was taken to hospital with serious injuries where he remains in a critical condition."
West Midlands Roads Twitter account posted shortly before 7am, warning people of the disruption, saying Station Road, Vicarage Road, Victoria Road, Coronation Road were all affected.
Soon after 8.30am the Transport for West Midlands-affiliated account tweeted: "Road closures remain in place #Pelsall. Very heavy traffic on surrounding routes through Pelsall Common."
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