SYDNEY • High-risk terror offenders may be kept in jail after their sentences finish, Australian officials said yesterday as they move to tighten security laws following attacks in the United States and Europe.

"In the wake of Orlando, Nice, and other terrorist incidents, as well as our own experience... we cannot afford for a moment to be complacent," Prime Minister Malcolm Turnbull said of the proposed changes.

"This legislation will enable additional periods of imprisonment for terrorist offenders who have served their sentences but are still judged to present an unacceptable risk to the community," he said in a statement.

The proposal, to be discussed with state and territory officials, who must then pass legislation, is similar to arrangements in place for sex offenders and violent individuals in some states.

Attorney-General George Brandis said the extension of detention would be a court-supervised process, with regular reviews and reassessments.

"It will of course only apply to individuals who, as they approach the end of a sentence of imprisonment, continue to pose an unacceptably high risk to the community because of their failure to be rehabilitated as a result of a penal sentence," he said.

Mr Brandis said the government would move to lower the age at which people can be subject to a control order - limiting a person's movements, communications and activities - from 16 to 14, and would also introduce legislation targeting hate preachers.

AGENCE FRANCE-PRESSE