Four workers have sustained minor injuries and have been hospitalised. (Representational)

Four persons were injured after a scaffolding erected for the construction of a major bridge in Goa across the Zuari river collapsed on Wednesday, an official said.

The incident occurred in the afternoon when the metal scaffolding supporting a concrete slab collapsed, injuring the workers at site.

"Four workers have sustained minor injuries and have been hospitalised. A probe has been initiated," a South Goa district administration spokesperson said.

In a statement issued, Dilip Buildcon Ltd, the infrastructure company which is constructing the bridge, said that "prima facie this scaffolding failure is most likely due to soil displacement from the (nearby) hillock".

"Thankfully, there has not been loss of blood, casualties... Dilip Buildcon prides itself on its impeccable safety and quality records. We have been working since April 2016, with an accident-free record," the statement said.

The eight-lane Zuari bridge connecting South Goa and North Goa districts is one of the poll promises of the Bharatiya Janata Party-led coalition government in the coastal state.