Senior members of the Comanchero outlaw motorcycle gang have been arrested in a series of early-morning raids across Sydney, police say.


Officers raided 10 properties across the city, including a Comanchero club house in Milperra.


"A number of arrests have been made, including high-ranking members of the Comanchero," police said in a statement.


The raids were carried out by officers attached to the Gang Squad's Strike Force Namara, which has been investigating alleged criminal activity of some Comanchero members, including commercial drug supply, firearms offences and the attempted bombing of a Milperra hotel.


In July last year, a cleaner for the Mill Hotel at Milperra stumbled across a sophisticated home-made bomb allegedly placed by a Comanchero bikie.


The hotel, previously the Viking Tavern, is where seven people died in a shootout between rival bikie gangs the Comanchero and the Bandidos on Father's Day 1984.


The bomb's timer stopped 17 minutes before exploding.


The search warrants across Sydney are ongoing.