It's the second fire at a Nomads club in the region in as many weeks.

crime scene has been set up at the Upper Hunter headquarters of the Nomads motorcycle gang after a suspected arson attack overnight.

Fire crews were called to the bikie club's unoccupied headquarters in Bridge Street, Muswellbrook around 2.30 (AEDT) this morning and contained the fire.

Two spot fires were still burning on the front porch of the building when police arrived ten minutes later.

Police say more information about how the fire started will be known once crime scene investigators from Newcastle assess the building later this morning.