A smoky three-alarm fire closed a major bridge over the East River on Tuesday afternoon, and five firefighters suffered minor injuries battling the blaze.

The fire on the Queensboro Bridge, which apparently started in scaffolding and a canvas tarp, produced heavy smoke that could be seen for miles.

Construction workers were painting steel on the upper deck when the fire erupted, according to Deputy Fire Chief Robert Sweeney. The tarp, used during sandblasting, suffered the greatest damage, he said.

More than 100 firefighters were sent to the bridge, also known as the 59th Street Bridge, which connects the boroughs of Manhattan and Queens.

"We needed a tremendous amount of manpower to get the water and the hose up to extinguish the fire," Sweeney said.

Traffic was stopped in both directions as firefighters arrived and vehicles were backed off the bridge.

The steel bridge, completed in 1909, spans the river between 59th Street in Manhattan and Long Island City in Queens.