Armed Crime Squad detectives are investigating a series of armed robberies and attempted armed robberies on Gaming Venues in the north-western metropolitan area.

Investigators believe the same group of men are responsible for 15 incidents which were committed between 7 December 2014 and 7 March 2015.

The incidents have occurred in Laverton, St Albans, Craigieburn, Roxburgh Park, Keilor, Brunswick and Epping.

Detectives believe up to four men were involved in each incident and entered each venue armed with shotguns, rifles, handguns and edged weapons, threatening staff and patrons at gun point.

The offenders stole various amounts of cash and fled the scene in vehicles which are believed to have been recently stolen.

During an armed robbery, on 18 February, the offenders left the scene in a stolen vehicle and a short time later and forced another vehicle from the roadway.

The female driver and her young daughter were threatened at gun point and forcibly removed from the vehicle before the vehicle was stolen.

Police have released still images and CCTV footage in the hope that someone in the community can provide information leading to the arrest of the offenders.

Armed Crime Task Force Detective Inspector Steve Clark said police were concerned about the escalating violence shown by the offenders.

“To drag a woman and her young daughter from a car is particularly violent and takes their offending to a new level.

“To threaten a woman and her child like this is particularly concerning and we need to get these men off the streets.

“These men are running through hotels with guns, threatening people, assaulting people, placing patrons and the public in significant danger

“If you think that you know who these men are we want to hear from you”

Anyone with information about any of these offences is asked to call Crime Stoppers on 1800 333 000 or submit a confidential report to www.crimestoppers.comm.au