It is estimated that there are as many as 260,000 illicit guns in Australia.

Justice Minister Michael Keenan said illegal guns were used in recent terror attacks in Australia as well as for organised crime.

As a result Australia is bringing in its first national gun amnesty since 1996 because of the growing terrorism threat and an influx of illegal arms in the country.

During the three-month amnesty running from 1 July, people can hand in unregistered weapons without the fear of prosecution, the government says.

Those caught outside that period face fines of up to A$280,000 ($212,730; £166,480) or up to 14 years in prison.

"This is an opportunity for people to present the guns to authorities, no questions asked and with no penalty," Keenan said.

"If people don't take that opportunity, the penalties for owning an unregistered or illegal gun in Australia are very severe."

Australia brought in a similar amnesty deal after the 1996 shootings in Port Arthur.