Customs and Border Protection says it detected double the amount of illicit drugs and weapons last year compared to 2011.

Officers confiscated more than three tonnes of illicit drugs and seized 1,100 firearms and nearly 250,000 other weapons.

Customs spokesman Tim Dawson says the department is making better use of technology and undercover officers.

"We're working beyond the border before anything reaches the border," he said.

"Our officers are using technology to build and share an intelligence picture with our partners internationally and domestically to directly target criminal activity.

"And because of that we have a far more targeted and effective approach."