AN INVESTIGATION has been launched following a fire which gutted a popular Southampton restaurant. 

The roof of 7Bone Burger has collapsed after a blaze tore through its branch in Portswood Road last night.

A major emergency operation involving 75 firefighters from across the county lasted into the early hours of today.

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Hampshire Fire and Rescue Service has secured the area, however, an investigation crew is now carrying out enquiries to determine the cause of the blaze, which is currently unknown.

Police have confirmed that it is not being treated as suspicious.

A spokesperson for the county force has said that officers assisted with road closures last night.

Portswood Road has since reopened but a cordon remains in place around the 7Bone building.