Terror suspects should be forced to wear tracking devices for at least two years if they return to Australia from known extremist hotspots, a leading security expert says.

The proposal comes after the Paris and Sydney attacks raised concerns about the ability of intelligence agencies to monitor every person suspected of terror links.

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Professor Clive Williams from the Centre for Policing, Intelligence and Counter Terrorism at Macquarie University said tracking technology used to monitor sex offenders could help.

“There are some very sophisticated tracking devices now available which can even be used to limit internet access for example,” he said.

“That would mean one security person could monitor as many as 20 persons of interest.”

He said it was possible to implement the tracking devices for suspects under current security laws.

“Under the control order system, which is good for a 12-month period, you can make a person wear a tracking device,” he said.

“And you can also require under the control order that they remain in a particular place, or they don’t go to a particular place or have association with particular people.

“So there are some quite strong measures within the system that I think we could be making more use of to keep better surveillance of people we have concerns about.”

He said close surveillance of a suspect could require up to 20 people working in the field and that was not always practical under staffing arrangements.

Professor Williams said Australian authorities should follow the lead of United States and UK counterparts who made greater use of tracking devices.

Foreign Minister Julie Bishop was reluctant to be drawn on the idea during an interview.

“I’ll leave that to our experts,” she said.

Ms Bishop said the passports of 80 suspected foreign fighters had already been cancelled using new laws.