Police have confirmed the fire on Tauranga Eastern Link bridge at the State Highway 2 and Domain Road interchange is being treated as arson.

A site examination this morning police has verified this claim, and police are asking the community to provide any information, including photos or video taken before or during last night's fire.

The Tauranga Eastern Link bridge this morning following last night's fire. Photo: Cameron Avery.

Polystyrene blocks used as packing in the overpass ramps caught fire at around 8pm last night, causing a spectacular blaze that spread toxic black smoke across the area.

Tauranga Police Detective Sergeant Darryl Brazier says police are continuing to work closely with fire officials to establish the cause in more detail, but based on initial information, an arson investigation has been launched.

Fire Fighters from Papamoa were called, and were backed up by crews from Mount Maunganui, Tauranga and Greerton as the extent of the fire became apparent.

The bridge construction site, which is part of the Tauranga Eastern Link Project, was significantly damaged by the blaze.

The site was closed at the time and thankfully no workers were hurt.

Darryl says the cost of the damage is considerable and is likely to impact significantly on the progress of the project.

It is thought the fire has caused up to $20 million worth of damage and there are fears the damaged section of structure may have to be pulled down and rebuilt.

'It was still daylight at the time of this fire, so someone may have seen something suspicious around the site at that time,” says Darryl.

'This was a very significant fire, so the person responsible is likely to have ‘bragged' about his/her actions.”

Police would like to hear from anyone who may have knowledge of this fire or who is responsible for this intentional criminal behaviour.

Anyone with information is asked to contact Detective Sergeant Darryl Brazier on: 07 213 0417.

Information can also be provided anonymously to the organisation Crimestoppers on: 0800 555111.