Fire crews were called to Rolfe Street at 1.45pm after receiving reports of a serious fire in a commercial garage and tyre fitter's premises.
West Midlands Fire Service said that 16 firefighters – made up of four crews from two fire engines and two brigade response vehicles - were tackling the blaze.
The organisation said in a statement: "This incident involved a fire in a tyre and car repair unit. Six breathing apparatus, one hose reel jet and two main jets were in use across the site.
"Good progress is being made, although the service bay was destroyed and there is heavy smoke logging to the affected unit. West Midlands Police is assisting our crews with maintaining a cordon around the site.
"We can confirm Rolfe Street has re-opened to traffic and allows businesses in the area to continue trading."
Later a fire service spokesman said: "At 1.48pm on Wednesday 27 September, West Midlands Fire Service were called to reports of a severe fire on Rolfe Street, Smethwick. Due to the scale and nature of the fire, we mobilised four fire engines and one brigade response vehicle to the incident from Handsworth, Ladywood, Smethwick and West Bromwich Fire Stations.
“Crews encountered a severe fire in a garage workshop and tyre fitters, which was sectorised to help crews best manage the incident. Because of the scale of the incident, Rolfe Street was closed, with West Midlands Police in attendance to support the incident. Crews used breathing apparatus, hose reel jets, main jets and a 9 metre ladder to bring the fire under control.
“Some crews will remain in attendance to monitor for hotspots and respond if needed, and Western Power Distribution and Cadent Gas are in the process of making the premises safe. Rolfe Street was reopened at 3.45pm.”
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