A teenager from Maryborough in Queensland's Wide Bay region has been charged following an investigation by counter-terrorism detectives into alleged plans to cause serious harm.

Police allege the 14-year-old was preparing to cause death or grievous bodily harm and had possessed material classified as violent extremist content. He has also been charged with possessing a knife in a public place.

The investigation began after counter-terrorism detectives executed a search warrant at a Maryborough property on August 27. During the search, officers seized several electronic devices and other items as part of their investigation.

According to police, the teenager allegedly planned to threaten people in Maryborough. Authorities have not identified any specific victims publicly, and details about the alleged plans remain before the courts.

Police have stressed that there is no current threat to the wider public connected with the investigation. The investigation remains ongoing as detectives examine information and evidence gathered during the search.

The teenager was expected to appear before Brisbane Children's Court on September 22. Because the accused is a minor, restrictions apply to the publication of information that could identify him.

The case highlights the work of specialist counter-terrorism investigators in responding to allegations involving young people and potentially harmful extremist material. Investigators can examine electronic devices and other evidence when assessing whether criminal offences may have occurred.

The charges against the teenager are allegations and have not been proven in court. The court process will determine how the matter proceeds and whether the allegations are ultimately established.

Police have not suggested that the wider Maryborough community is facing an immediate danger from the case. Residents have therefore not been advised to take any special action in response to the investigation.

Maryborough is a regional Queensland city located on the Mary River, north of Brisbane and close to the Fraser Coast. The city has a population of more than 27,000 people and serves as an important regional centre for surrounding communities.

The investigation is expected to continue while authorities assess the material seized during the search and other information gathered by detectives.

Police have encouraged members of the public who become aware of suspicious activity or information relevant to an investigation to report it through appropriate channels rather than taking matters into their own hands.

The teenager's next court proceedings will determine the future direction of the case. As with all criminal matters, the allegations must be considered through the appropriate legal process.

Authorities have not released additional information that could identify the teenager or provide operational details about the alleged plan.