An 18-year-old man has been charged in Sydney after detectives allege he operated a drone to conduct surveillance as part of an alleged conspiracy to murder.

The arrest follows an investigation by Taskforce Falcon, Raptor Squad and the Homicide Squad into an alleged organised criminal plot in Sydney's south-west.

NSW Police said Strike Force Naleto was established to investigate the alleged conspiracy. Two men, aged 18 and 19, were initially arrested in West Hoxton on September 11 and subsequently charged.

A 28-year-old woman has also been charged in connection with the investigation and remains before the courts.

Following further inquiries, detectives arrested another 18-year-old man at Silverwater at about 8:50am on September 28.

Police allege the teenager was operating a drone to conduct surveillance connected with the alleged plan. The investigation is examining the purpose of the surveillance and the teenager's alleged involvement in the broader criminal group.

The teenager has been charged with conspiring and agreeing to murder a person, participating in a criminal group and contributing to criminal activity. He was also charged with possessing a digital electronic communication device for the purpose of serious criminal activity and allegedly failing to operate an unmanned aircraft within visual line of sight.

The teenager was refused release and was due to appear before Bail Division Local Court 6 on September 29.

Police have not alleged that the teenager carried out a murder. The charges relate to the alleged conspiracy and activities investigators say were connected to it.

The investigation remains active, with detectives continuing to examine the alleged criminal network and the roles of people already charged.

The case also highlights the use of drones in organised crime investigations. While drones have become widely available for recreational and commercial purposes, NSW regulations require operators to follow aviation safety rules, including requirements concerning visual line of sight.

Police allege the drone in this investigation was used for surveillance rather than an ordinary recreational purpose. Detectives are continuing to examine evidence gathered during the investigation.

The arrests form part of wider police efforts targeting organised criminal activity in Sydney's south-west. Taskforce Falcon works with specialist police units, including Raptor Squad and the Homicide Squad, on serious investigations.

The investigation remains ongoing and further charges are possible. The allegations against the accused people have not been tested in court, and each accused person is entitled to the presumption of innocence unless proven guilty.