The president of the Comanchero bikie gang has been arrested over an alleged bombing attempt at a Sydney hotel.
Eight senior members and associates of the gang have been arrested, including the club's president.
In July last year, a staff member of The Mill hotel, at Milperra, found a device at the front door about 7am. At the time, the hotel was closed to patrons, but about 20 guests were staying on the premises.
Police say the timer of the sophisticated device stopped 17 minutes before it was to detonate.
Police on Tuesday said if the device had exploded it could have caused major damage to the hotel and significant loss of life.
"We're not dealing with boy scouts with these groups," Detective Acting Superintendent Gavin Wood of the gang squad told reporters in Sydney.
"We're dealing with serious organised crime figures."
The Comanchero president could be facing charges of handling explosives in relation to the alleged bombing attempt while others are facing drugs and firearms charges.
Comanchero member Samy Duong was charged in November last year with placing the device at the door of the hotel.
Strikeforce Namara commenced in January to investigate alleged criminal activity of the local bikie chapter.
Police expect to make more arrests in connection with Tuesday's raids.
"We still have a number of doors to knock on," Acting Supt Wood said.
"We still have a number of shoulders to tap."