Officials are now investigating what caused a fire at a former pizza shop in Vallejo early Thursday.

The fire was reported just before 4:30 a.m. at Straw Hat Pizza on Sonoma Boulevard near Redwood Street. 

It took crews just under an hour to get the fire under control. 

The pizza joint has been closed for at least the last 5 years.

Authorities say there have been several fires here over the years, started by squatters. 

There were no reported injuries.

Check back for updates. 

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